Fresh from declaring neoconservatism "a governing ideology whose time has come," Charles Krauthammer calls for "situational libertarianism," which he defines like this: "Liberties should be as unlimited as possible—unless and until there arises a real threat to the open society." At which point he supports "every measure of harassment and persecution from deportation to imprisonment." So he actually favors situational repression, but I guess that doesn't sound as good.
Civil libertarians needn't worry about a slippery slope, he continues, because "there is no slippery slope, only a shifting line between liberty and security that responds to existential threats." He expands the thought in this remarkable passage:
During the Civil War, Lincoln went so far as to suspend habeas corpus. When the war ended, America returned to its previous openness. During World War II, Roosevelt interned an entire ethnic group. His policies were soon rescinded (later apologized for) and shortly afterward America embarked on a period of unprecedented expansion of civil rights. Similarly, the Vietnam-era abuses of presidential power were later exposed and undone by Congress.
Our history is clear. We have not slid inexorably toward police power. We have fluctuated between more and less openness depending on need and threat.
Got that? The wartime oppression of the past, from the internment of Japanese Americans to Nixon's abuses, was simply a response to "need and threat." And if you were treated unjustly—say, if you were locked up for years because you have the same skin color as Tojo—then … well, you'll get an apology later on. Hey, we all have to make sacrifices. Get with the program, mister!
Meanwhile, since when was irreversibility a part of the slippery slope argument? Krauthammer essentially posits that a slope isn't slippery if we've managed to reclimb it, a position that misses the point on so many levels that I hardly know where to begin.
Instead, I'll just note that very few of the country's wars were even arguably fought against a threat to our open society, unless you seriously want to claim that Kaiser Wilhelm or Ho Chi Minh had designs on the American mainland. In the United States, the most persistent threat to the open society has been war itself, because it gives people like Krauthammer an excuse to prune the Bill of Rights. If I were the situational sort of libertarian, I guess I'd start hollering just about now to send Charles K. to Guantanamo Bay.