Editor's Note: This column is reprinted with permission of the Washington Examiner. Click here to read it at that site.

Sick of Hollywood's standard superhero fare? You could do worse than to take in J. Edgar, the new Clint Eastwood-directed biopic about the legendary FBI director who served eight presidents over nearly five decades.

"Served" isn't quite right—Hoover mainly served himself, and the dossiers he compiled through his agency's spying on top political figures made presidents fear to replace him, lest he, as Richard Nixon put it, "pull down the temple" in retaliation.

If, like me, you've been unconvinced by Leonardo DiCaprio's career transition from teen heartthrob to action hero, you may be surprised by how good he is here as an aging bureaucratic martinet, bent on eliminating all obstacles to his control.

And, at its best, the movie is a powerful cautionary tale about the dangers of government surveillance.

For my money, however, it spends too much time on Hoover's relationship with top aide and lifelong companion Clyde Tolson—an unconsummated romance, per Eastwood's take. The implication—that Hoover's (alleged) repression drove FBI oppression—muddles an important message with Freudian psychodrama.

After all, plenty of FBI agents with conventional family lives embraced COINTELPRO, the bureau's domestic espionage program, and presidents like Jack Kennedy and Lyndon Johnson, who were, let's face it, hardly sexually repressed, were themselves enthusiastic wire-tappers.

When the steel industry raised prices in 1962, JFK and RFK ordered wiretaps on company executives and had FBI agents carry out dawn raids on their homes.

''Lyndon Johnson was the most demanding'' when it came to requisitioning FBI political intelligence, federal judge Laurence Silberman discovered in 1974, when, as a deputy attorney general, he was tasked with reviewing the late Hoover's secret files. At Johnson's request, the FBI even bugged presidential candidate Sen. Barry Goldwater's campaign plane.

Hoover's hang-ups, whatever they might have been, weren't the problem. The problem was, as a Senate Select Committee investigating intelligence abuses concluded in 1976, that "intelligence activities were essentially exempted from the normal system of checks and balances.... such Executive power, not founded in law or checked by Congress or the courts, contained the seeds of abuse and its growth was to be expected."

In a two-year investigation, the Church Committee discovered just how deep the rot at the FBI ran. The COINTELPRO program went far beyond mere surveillance, with agents burglarizing homes and planting "evidence" designed to discredit "subversive" groups (broadly defined).

On one occasion, FBI agents kidnapped an antiwar activist to intimidate him into silence. On another, agents bugged Martin Luther King Jr.'s hotel rooms and sent him a tape containing evidence of his extramarital affairs.

With the tape was a letter saying ''King, there is one thing left for you to do. You know what it is''—that is, commit suicide.

As the movie shows, in Hoover's day, domestic spying was a comparatively low-tech affair, a matter of index cards, and on-site wiretaps. Today, modern processing power and data-mining technology have dramatically enhanced federal spying capabilities, and post-Hoover legal restraints have been steadily weakened in the wake of 9/11.

The Justice Department's latest report to Congress shows that a record 14,212 American citizens and permanent residents had records of their financial, telephone and Internet activity seized by the FBI last year through extrajudicial National Security Letters.

That's not to suggest that the agency is currently engaged in Hoover-era criminality. But it's worth considering that, as my colleague Julian Sanchez points out, "the existence of such large databases in itself increases the risk of abuse."

"Information is power," Hoover intones in one of the film's key lines—and history warns us that power unchecked becomes power abused.

Gene Healy is a vice president at the Cato Institute and author of The Cult of the Presidency: America's Dangerous Devotion to Executive Power (Cato 2008). He is a columnist at the Washington Examiner, where a version of this article originally appeared. Click here to read it at that site.