The Volokh Conspiracy
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No, Trump is Not Making Separation of Powers Great Again
He's more than happy to engage in power grabs when it helps his agenda.

In recent weeks, even some commentators who are not normally sympathetic to President Trump have praised him for supposedly restoring the separation of powers. They include legal scholar Josh Blackman, former American Enterprise Institute President Chris DeMuth, and Matt Welch of Reason, among others. The main point they make is that Trump and his appointees have cut back on some regulations, and promise to avoid imposing new regulations through "guidance letters" that circumvent the normal regulatory process. DeMuth even goes so far as to claim that Trump has "proved to be a full-spectrum deregulator" and that "[h]is administration has been punctilious about the institutional prerogatives of Congress and the courts."
The Trump administration has indeed produced some useful deregulation. One particularly noteworthy example is their withdrawal of a proposed Obama rule banning the sale of hematopoietic stem cells that contain bone marrow, a change that could save many lives. Overall, however, Trump has done far more to undermine constitutional constraints on presidential power than strengthen them. A "full-spectrum deregulator" he is not. Much the contrary. Trump is more than happy to breach constitutional limits whenever it might help advance his agenda.
Consider the administration's efforts to punish sanctuary cities, jurisdictions that refuse to assist federal efforts to deport undocumented immigrants. As federal judges of both parties have repeatedly ruled, Trump's and Attorney General Jeff Sessions' efforts to target sanctuary cities undermine both federalism and separation of powers. By imposing new federal grant conditions that were never authorized by Congress, the administration is attacking legislative control of the power of the purse, and also potentially creating a powerful tool by which the executive can pressure states and localities. I summarized the dangerous implications here:
Longstanding Supreme Court precedent indicates that only Congress can impose conditions on grants given to states and localities, and that those conditions must be "unambiguously" stated in the text of the law "so that the States can knowingly decide whether or not to accept those funds…."
Should the administration manage to get away with [its efforts to impose new grant conditions], it will set a dangerous precedent that goes far beyond… the specific issue of sanctuary cities. If the president can unilaterally add new conditions to one federal grant program, he can do the same thing with others. This would give presidents a massive club to coerce state and local governments on a wide range of issues….
Some conservatives may cheer when the current administration uses this tool against sanctuary cities. But they are likely to regret their enthusiasm if a liberal Democratic president uses the same tactic to force states to increase gun control, adopt a "common core" curriculum, or pursue liberal policies on transgender bathroom accommodations.
Allowing the executive to impose its own after-the-fact grant conditions also threatens the separation of powers. It goes a long way towards taking control over spending away from Congress and transferring it to the president. This, of course, violates the text of Article I of the Constitution, which clearly gives the power of the purse to the legislature, not the executive.
Trump and Sessions' asset forfeiture policies represent another attack on federalism, in that they undermine state and local governments' control over their own police forces. They also undermine due process by incentivizing law enforcement agencies to seize the property of people who have never been charged with any crime, much less convicted, often failing to give owners a meaningful opportunity to challenge the seizures. Seizing property without due process is a classic example of executive overreach.
Trump's immigration policy also belies the notion that he is a "full-spectrum deregulator" respectful of the prerogatives of Congress and the courts. It has resulted in a crackdown which undermines liberty and due process for both new immigrants and American citizens. Trump's travel ban "proclamation" is not only motivated by unconstitutional religious discrimination, but also openly discriminates on the basis of nationality, in direct violation of a law enacted by Congress. Here too, it's difficult to find much in the way of respect for separation of powers.
Trump's rule by unconstitutional executive orders and proclamations is no better than Obama's government by guidance letter. In some respects it is even worse. Unlike Trump's orders, Obama's guidance letters were, at least in principle, not supposed to be legally binding.
Perhaps worst of all, Trump has doubled down on Barack Obama's most dangerous breach of the Constitution: waging a war initiated without congressional authorization. In October, Secretary of Defense James Mattis and Secretary of State Rex Tillerson testified to Congress that the administration does not need any congressional authorization to continue the war against ISIS - which Obama began and continued without congressional authorization. The Trump administration has endorsed Obama's implausible claims that the war is authorized by previous congressional resolutions aimed at entirely different adversaries. In August, Trump threatened to rain down "fire and fury" on North Korea in response to its potential threats - without betraying any recognition that initiating a new Korean War would require congressional authorization.
Even when Trump ultimately does the right thing on separation of powers issues, it is usually more a matter of short-term political expediency than a true restoration of constitutional constraints. For example, Trump was right to put an end to illegal Obamacare subsidies that had not been authorized by Congress. But he did so only after a failed effort to use the subsidies as leverage to extract concessions from Congress. The message here is not that the president won't spend money without congressional authorization, but that he will only do it when it might be politically advantageous. In this instance, Trump is like a thief who claims to be reformed, but actually only stopped stealing because he no longer wanted particular type of stolen property.
Finally, there is the matter of Trump's open disdain for "so-called judges," freedom of the press, and other constitutional constraints on his power. It is easy to dismiss all of this as mere words. Who cares what Trump says on his Twitter account? But such dismissals ignore the fact that adherence to constitutional limits on government power depends on norms, not just judicial decisions or formally enacted policies. When those norms are undermined - especially by the most powerful government official in the land - future breaches of the Constitution become more likely - and more thinkable. A political culture that accepts presidential disdain for the judiciary or for freedom speech, is one that becomes less likely to curb future abuses of power.
In one sense, of course, Trump's bad behavior may strengthen the separation of powers in the long run. It might lead Americans to have a greater appreciation for the need to constrain presidential power. I hope that happens. But I very much fear that, instead, Trump's abuses will serve as precedents for similar or worse ones by his successors - just as Trump himself has built on those of Bush and Obama. That is all the more likely to happen if Trump manages to get away with his abuses without paying a substantial political price. Ironically, therefore, the best way to make sure that Trump helps make separation of powers great again is to recognize that he is actually trying to do the opposite, and penalize him for it.
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So, immigration, mostly. Not surprised.
Yeah, I'm not happy about the forfeiture, either. But the answer to that is repeal of those laws, no?
Ilya is nothing if not a broken record. I appreciate where he comes out on immigration but... yeah, you shouldn't expect him to write on anything except a handful of his favorite topics.
Just an intro of his Libertarian greatest hits to the new Reason audience (some of whom actually are Libertarian versus the more standard right wing partisans who flocked like self-destructive moths to the flame of WaPo).
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Nothing to see here, move along.
It will be interesting to see whether the Conspiracy's genuine libertarian fares better among commenters at Reason than he did among the right-wingers and faux libertarians who blistered him at the Post.
It also will be interesting to observe how Reason's audience reacts when the Conspiracy's movement conservatives unpack their boxes from the move and don their libertarian drag.
There is something unique and special about being authoritarian on immigration, because it's just super important, unlike that other stuff that the President wants to deregulate, which is unimportant, except deregulating it is really important.
Immigration stirs up racists and nationalists in the base. You're smarter than that, so I suspect this is all about preserving a perpetual Republican majority, and immigration poses a threat to that. Since you believe Republican government actually is more moral, that's not an offensive position. But at least with Gerrymandering Republicans are honest about the intent. For immigration and voter fraud, Republicans just lie about or manufacture problems, because they don't have the stomach to publicly state what those policies are really about.
Most people understand that, without borders, you don't have a country. And even Ilya isn't totally opposed to border enforcement, I assume; Though he's never confirmed it, I'm guessing he'd make an exception for large groups of identically dressed, armed immigrants crossing the border in formation.
Or perhaps he'd insist that nothing be done until they opened fire?
See, as my generation of libertarians understood, you can't get together to do something, (Including getting together to be free.) if you can't exclude people who don't want to do that something.
And, rather critically, there's that little path dependence in implementing libertarianism: Even if a nightwatchman state could afford free immigration, a welfare state can't, and we are still a welfare state. Worse: We're a welfare state next to a third world country!
So, in a welfare state, what is the better way to control immigration's costs? Is it to ramp up enforcement, require every employer to verify legal status, infringe upon rights to privacy along all borders, coasts, and international entry points, conduct countless raids and maintain an archipelago of detention facilities for immigrants being "processed," and on and on, all to try to fight a black market of labor and human trafficking that nonetheless springs up? Or is it to treat illegal immigration as the administrative problem that it actually is, onramping voluntary, otherwise lawful, and productive immigrants into our society and economy in the least disruptive way possible?
You would consider another nation's military crossing our border an immigration issue? That has got to be the hottest take I'll see all day. I hope.
I'm not advocating for open boarders, the Democratic platform does not call for open boarders, etc.
We've had porous boarders and a welfare state long enough to know the experiment isn't fatal. Much welfare isn't available to illegal immigrants, and it just isn't the case that rivers of people pick up from their homes so they can move somewhere to just sit around and collect a check. I doubt anybody works harder for less in America than illegal immigrants. That doesn't mean they're entitled to stay, but Milton Friedmon's thoughtful welfare/open boarders point never materialized. It's Peak Oil at this point.
It is easy to say that states and local jurisdictions, under principles of federalism, have a right to conduct their local affairs as they see fit without interference from the federal government. But states that encourage illegal immigrants to locate there are also increasing their representation in the House of Representatives and in the Electoral College, which the rest of us have a right to object to.
Does that same reasoning apply to states that try to restrict abortion or inhibit the sale of contraceptives?
I'd love to hear this, aluchko: how does restricting abortion create rotten boroughs?
Swood1000: States use illegal immigration to swell population numbers and increase the power of their vote in Congress.
alchuko: Restricting abortion and contraceptives also increases population and Congressional representation.
HTH
You don't know what a "rotten borough" is, do you
*spoiler* anyone born in the United States cannot be part of that problem in the United States, so abortion and birth control rules in the United States can't create them*spoiler*
Yes, "sanctuary cities" were just a plot to game the once-every-decade redistricting process, to obtain slightly more representation in the House...
Let's face it. You can't diss California without picking up Texas, Florida, and all the southern border states in the same broad sweep. You think Texas isn't encouraging illegal immigration. Maybe not, but where do you think those blue counties are... hmm...?
Anyway - never fear, Trump is sure to politicize and de-fund the next census, so the ongoing plot to undermine the franchise in this country is full-steam ahead!
It isn't just representation in the House. It's also representation in state legislatures, and a great many programs that provide funding based on population.
The idea that anyone wants to provide sanctuaries to undocumented immigrants just to game the redistricting process or obtain more money is just without merit. There are plenty of much more-salient reasons why you'd implement sanctuary policies or encourage immigration.
I live a sanctuary city. I want it to remain a sanctuary city because I don't want the parts of the city where immigrants live to become unsafe or impoverished, which they will become if their residents no longer feel safe calling the police for minor crimes or making use of public assistance. I also believe that free immigration and movement of labor is beneficial to the local and regional economies. It has nothing at all to do with obtaining greater representation in state or federal politics.
Then I assume you'd support a change in the law, so that illegal immigrants no longer counted for purposes of apportionment?
Maybe we could compromise and count only three-fifths of them.
So you were being dishonest when you said it has nothing to do with obtaining greater representation.
No. I think it makes sense, from a policy and philosophical perspective, to include undocumented immigrants in our tallies and apportionment decisions. What I said was that those kinds of considerations aren't what drive the decision to be accommodating to immigrant communities.
What I said was that those kinds of considerations aren't what drive the decision to be accommodating to immigrant communities.
No, it isn't what you said. "It has nothing at all to do with obtaining greater representation in state or federal politics."
Either that's true and you don't care one way or the other so there is no reason not to accept Brett's proposal, or it's false
No, it isn't what you said.
And then you quote me saying exactly that.
Look, I don't know what kind of gotcha you think you've got me in here, but you need to separate two normative questions: whether cities and states should have accommodating policies for residents that are undocumented immigrants, and whether apportionment decisions should track where people lived, or just where legal residents live. It's only in the undereducated miasma of the conservative mind that the two seem inextricably linked.
Interesting that Simon's position and response are directly in line with the slave holder colonies when the Constitution was written. Not surprising as that is the same method used by Progressives running plantations in slave States as well as continuing the same ideology only transferring the control to Progressive government run plantations with Elitist Masters and Uncle Tom Overseers.
The difference being, of course, that I support broader citizenship and fuller incorporation into American society of undocumented immigrants, as well as their inclusion in tallies and apportionment decisions. It's conservatives who want to maintain second-class citizenship for them, while at the same time exploiting their labor and impoverishing their communities.
I'm sure the Chamber of Commerce Republicans in Texas supporting illegal immigration are just in it for the long con of increasing the state's representation in the House. Joe Arpaio was actively trying to lower Arizona's representation in the house. If you didn't count illegal immigrants,
Maybe we should amend the Constitution to not count illegal immigrants.
States that also volunteer for prisons to be located in their states increase their population count without any corresponding changes in voting demographics.
Of course, there are what, 50 times as many illegals as federal prisoners?
Be advised: the items printed in orange are almost unreadable.
Unfortunately, I believe that they went back to the old Volokh Conspiracy formatting. I'm not a fan of orange hyperlinks, Helvetica font, and 10.5 typesize. The Washington Post was a much more readable, professional site. Blue hyperlinks, Georgia font, and 13.5 typesize was a very good choice. I shall miss it very much.
But you are correct, this is almost unreadable.
B-b-but... curse words! Freedom!
I'll second that...had to increase my font size overall just to read the link text (annoying because it reduces the total amount of content per page).
On further reflection, I wonder if whoever settled on orange for some text doesn't have a color vision problem that makes it look darker to him. Also, 'edit' and 'like' functions are needed, and I hope on the way.
I could live with Disqus, too.
"Overall, however, Trump has done far more to undermine constitutional constraints on presidential power than strengthen them. A "full-spectrum deregulator" he is not. Much the contrary. Trump is more than happy to breach constitutional limits whenever it might help advance his agenda."
If President Trump can overcome constitutional barriers, then they aren't barriers at all. These issues are being worked out in court and they are far from being matters of settled law, if there is such a thing. In his defense, every president has done what he could to expand executive power; it's nothing new.
I'm saying this as a person who didn't vote for Trump and who gives him a solid D? grade for his tenure so far. He is not a conservative by any stretch of the imagination. What happened in 2016 to the Republican party was a hostile takeover by people who allowed their anger to overshadow their reason. If I remember correctly, you are big on political ignorance.
The author works hard to find the rotten apple in the nice, new barrel of fresh apples.
Yes, Trump isn't perfect on separation of powers. This is hardly a surprise.
But, compared to Obama, he is a breath of fresh air.
So how about celebrating all the fresh apples, not the rotten one. For once. Please? #NeverTrumpers get tedious.
Ilya has his pet proclivities, and any imposition on those proclivities is a gross violation of some very important larger rule. And anything outside of those proclivities is irrelevant or at best unimportant. Well, bless his heart, at least he's consistent. Of course, it does often make him repetitive, boring, and whatever the opposite of insightful is.
He's kinda like Shika that way.
But, compared to Obama, he is a breath of fresh air.
The irony being, I suppose, that it's only a matter of time before the EPA's soft-pedaling on enforcing our laws on air pollution will make that "fresh air" a thing of the past.
I'm curious: Do you reject the idea of diminishing returns as a theoretical matter, or just assume that people who want to roll back regulations won't stop short of repealing them all?
Because the EPA solved the problem of "fresh air" decades ago, not last week.
I assume only that an EPA administrator more interested in spending taxpayer money to go on elaborate Moroccan vacations with his staff to promote the natural gas industry than enforcing the regulations on the books is going to preside over a decrease in air quality. Maybe not next week, maybe not nationwide, but point-by-point, I think we'll start to see stories about polluters getting away with more than they used to.
Never mind that the regulation of carbon dioxide emissions is nowhere near "solved." You may not like that the EPA is legally required to address such emissions and may believe that Congress should amend the Clean Air Act so as to remove carbon dioxide from the EPA's mandate. But as it stands, the law requires the EPA to do something about it.
The EPA's brief is a clean environment, not climate control. CO2 isn't toxic until you reach concentrations enormously higher than any that are at all likely, (About 3 times present levels.) which is a darned good thing, because they get quite high indoors. "Fresh" air is fresh in Alaska and here in South Carolina, despite the radically different temperatures.
The EPA *might* have a basis for regulating CO2 even deprived of it's climate change excuse, though: While outdoor levels of CO2 are extremely unlikely to reach toxic levels, they could eventually reach levels where there's little headroom for indoor CO2 to exceed the outdoor levels without biological effects. At that point the EPA would have a colorable excuse to regulate CO2 as an actual pollutant.
Like I said, you might not like to believe it, but the law on this point is now ten years old. The Clean Air Act requires the EPA to regulate carbon dioxide, based on its own findings that carbon dioxide emissions - yes, through climate change - are impacting human welfare. Congress could change that. The EPA could violate the law and ignore its own findings and analysis (which appears likely to be Pruitt's preference, as it was during the Bush II years). But that's the law as it currently stands.
Go cry about it.
The clean air act doesn't require the EPA to regulate CO2 at non-toxic levels. It doesn't even mention CO2.
It may take some legal work to reverse this, as the EPA conspired with environmental groups to be placed under a court order to treat CO2 as a pollutant, the "Sue and Settle" scam. But it is not "the law", in any legitimate sense.
Wow, you must be nuts. The EPA was sued by Massachusetts during the Bush II years, and the "court order" you're talking about is a Supreme Court ruling. That's pretty much as legitimate as you get, when it comes to what "the law" is.
The only way to reverse that is to get Congress to pass a statute or the Supreme Court to reverse itself. But until that happens, it's absolutely legitimate law - in the real world, anyway, and not the fantasy realm in which some libertarians somehow think a Lockean moral law truly reigns.
The author works hard to find the rotten apple in the nice, new barrel of fresh apples.
Yes, Trump isn't perfect on separation of powers. This is hardly a surprise.
But, compared to Obama, he is a breath of fresh air.
So how about celebrating all the fresh apples, not the rotten one. For once. Please? #NeverTrumpers get tedious.
It's hard to tell what Trump will do from day to day. He's certainly not a constitutional conservative. Yet the violations he's doing are either bipartisan or analagous to what the other party did.
As for imposing extra limits on federal funding, see the "Dear Colleague" letter which Trump rolled back.
Eidde, IIya addressed the "Dear Colleague" issue in the article:
"Trump's rule by unconstitutional executive orders and proclamations is no better than Obama's government by guidance letter. In some respects it is even worse. Unlike Trump's orders, Obama's guidance letters were, at least in principle, not supposed to be legally binding."
One really should read the entire article before commenting.
With the single exception of Jimmy Carter, all presidents beginning with FDR have sought to increase presidential power at the expense of Congress. The imperative to do so is not partisan; it is institutional. Any resistance depends exclusively on the willingness of Congress to push back, a willingness that has been missing in action for generations. I leave to others the judgment of whether we are better or worse off because of the aggrandizement of executive power, but it is a fact of constitutional life that has little to do with the ideology of the president in power.
I agree. Over the last several years, the gradual (and sometimes not so gradual) expansion of Presidential powers has concerned me. That's one reason the courts' rejections of selected Obama Executive actions in the last few years of his Presidency was probably overall a good thing (whether I agreed or disagreed with the specific actions in question).
That's because they set a precedent that came into play in different courts similar rejection of Trump's similar attempts (Travel Ban and Sanctuary City--though their final results are still to play out--and others sure to come up).
What is often missed, in all the ballyhoo-ing about Trump's so-called "rollback of the regulatory state," is the fact that even such "rollbacks" are constrained by legislation, and must be done in accordance with requirements imposed by Congress. It shouldn't count as "separating powers" again if Trump's rollback of regulatory authority is in direct contravention of congressional direction, which all too often it quite clearly is. You can't just declare the Clean Power Plan no longer law, for instance; you have to go through notice-and-comment rulemaking, and more importantly, you have to justify your change in course. Those are all legitimate restraints on executive authority, imposed by Congress, that Trump (or, really, his rotten subordinates) is ignoring on issue after issue.
When you look closely at these much-celebrated "rollbacks," you'll find a lot of really squirrelly reasoning that makes a mockery of decades of administrative practice. It's like Mnuchin's amateurish one-pager explaining how "tax reform" will pay for itself. It's rank lawlessness and corruption, all the way through.
Perhaps worst of all, Trump has doubled down on Barack Obama's most dangerous breach of the Constitution: waging a war initiated without congressional authorization. In October, Secretary of Defense James Mattis and Secretary of State Rex Tillerson testified to Congress that the administration does not need any congressional authorization to continue the war against ISIS - which Obama began and continued without congressional authorization. The Trump administration has endorsed Obama's implausible claims that the war is authorized by previous congressional resolutions aimed at entirely different adversaries.
While I agree with a need to update or replace the AUMF, I'm curious about the actual law on the precedence of enemy bodies. Since ISIS is a development from AQI, against whom it was (apparently) accepted that the AUMF against Al-Qaeda allowed prosecution in 2003 (among the broader UN and US ceasefire agreements from Desert Storm, Desert Fox et al), what's the legal case on each side of the argument? I ask, again agreeing on the constitutional need for a proper declaration.
I find the AUMF against Al-Qaeda to be a bit tenuous given that Al-Qaeda still exists and hates ISIS. I think a much stronger argument exists that the AUMF in Iraq authorizes the US to intervene to protect Iraq and intervene in Syria to prevent ISIS from threatening Iraq again.
"Al-Qaeda still exists and hates ISIS"
Hamas hates Fatah but they have the same goal and still co-operate a lot.
Actually, Jones may do just fine by voting for things that actually help Alabamians, such as Medicare, Medicaid, Social Security, and against the Trump/GOP tax increase, and so on.
It would be interesting to see it argued in court that 'the power of the purse' has passed to the president through adverse possession. Because that's exactly what it's looked like for about the last twenty years, and just maybe stating the claim baldly would force the Congress to start doing its job again.
I did not vote for Trump, was shocked when he emerged as the front-runner in the GOP primaries, and remain disturbed by how he is changing basic norms of behavior for a President.....that said....in practical terms, his use of power is pretty consistent with past Presidents....and he has taken no real steps to breaking apart the legitimacy of the Courts, chilling media free speech, or over-running the checks of the legislature. His immigration EO is silly in my view and probably bad policy....but asserting it...revising it....and trying it as a signal is hardly the end of the world. The N. Korea situation depends on one's views on nuclear proliferation....and the security problems that might entail. Punting the ball down the field appears to be the standard option....but at what point is that no longer viable? No war ever...is less a policy than a bumper sticker. Trump is doing good things at the EPA, at the department of education, with energy and the Keystone pipeline, putting good conservatives on the bench, cutting corporate taxes, and exposing media hypocrisy....I would think a libertarian would more fully appreciate this...and not go off looking for evidence that the sky just might start falling...any minute now. Just sayin'
I notice you didn't mention the failed bombing by the Bangladeshi "immigrant." Why is that?
What does that have to do with separation of powers?
Unlike, say, Obama (and to a lesser extent, Nixon, Carter and Reagan), Trump isn't doing these things because Congress has frustrated his intentions. Congress is in Republican hands and would easily pass these orders in legislative form. Trump is simply lazy, or in fact doesn't understand how the federal government does things.
Trump is, of course, lazy and astonishingly incompetent and ignorant. But I think he prefers to do things unilaterally, because this way he can take credit for them, when and as he deems necessary. Every time he needs a boost to the ego, he rolls out another executive order which, by its terms, doesn't actually do much besides give him the opportunity to spin it as a major "win" for the base. And then Congress is more than happy to let him be the fall guy for failed policy - as will inevitably happen when everyone realizes how much of a scam this tax bill is.
Yes, quite true.
With Trump, who is not a mature adult, we have to reorient our Constitutional analysis. It's no longer about policy, or competing interests, or checks and balances. We have to start viewing things as a pediatric psychologist would. It's jarring and embarrassing, but that's what we have to do.
"would easily pass these orders in legislative form"
Not without breaking the Senate legislative filibuster, the can't. How do you get 60 votes for even the current travel order?
Expansion of federal power in an area where the federal government has the constitutionally granted right to exercise power is not a denial of "separation of powers" issue any more than the government expanding the U.S. military or printing paper money is a "separation of powers" problem.
In both cases you listed (sanctuary cities and immigration bans), the United States Federal Government, under Article I, section 8, clause 4, has the power to "establish a uniform rule of naturalization..."--meaning Trump's immigration ban and his attacks on sanctuary cities (which seek to bypass federal naturalization laws) may be an expansion of federal power--but it is most definitely not a "separation of powers" problem.
I mean, it'd be like you arguing the establishment of the U.S. paper money and the eventual banning of bank-issued money in the 1860's was unconstitutional since it represented the United States expanding its power under Article I, section 8, clause 5 against nearly a hundred years of established custom. (Yes, I know, paper money--and certainly computerized records as a proxy for cash--are not explicitly spelled out. But they were not explicitly denied by our founding fathers.)
You misunderstand Prof. Somin's argument. With respect to the attacks on sanctuary cities and the imposition of the travel ban, he's arguing that (to the extent that these things are constitutional) they require congressional authorization rather than a unilateral declaration by the White House. If Trump is assuming a legislative function by creating these rules, it is a separation of powers problem. (Article I, Section 8 authorizes Congress, not "the United States Federal Government," to establish a uniform rule of naturalization.)
Oh, and please note that although people tend to conflate immigration and naturalization, they are not the same thing, and the fact that Congress has the power to legislate with regard to naturalization does not automatically mean it has any power over immigration. To the extent it does, that power has traditionally been seated in the commerce clause rather than the naturalization clause.
(A) If Trump is acting in order to enforce existing immigration laws (which "sanctuary city" status seeks to thwart), then how does this require legislative action? Now if the legal framework covering immigration status were missing, then I'd agree with you.
(B) My understanding is that Article I, section 8, clause 4 establishes the Federal Government's authority not only to pass laws on naturalization, but also to pass laws on immigration. (Yes, I understand that "immigration" and "naturalization" are not the same thing. But unless you are attempting to argue the Constitution does not empower the United States to also regulate immigration under Article I, section 8, it seems the federal authority to manage immigration and naturalization pre-exists in the Constitution, and so the fed passing immigration laws is not a "separation of powers" problem.)
I'd be curious to see an actual analysis trying to weigh the good and bad instead of saying "I admit here's a good thing" but "here's a bunch of bad things".