Last week, the History Channel announced that Greg Kinnear and Katie Holmes have signed on to play President Kennedy and his wife in an upcoming eight-hour miniseries, The Kennedys. Kinnear, best known for playing the dad in Little Miss Sunshine, seems an odd casting choice, but the real controversy surrounds the series’ producer, Joel Surnow.

Surnow is the creator of 24, a pal of Rush Limbaugh’s, and one of the industry’s few prominent conservatives — which makes some liberals nervous about how he’ll handle a liberal icon.

Robert Greenwald, a left-wing documentarian who read an early version of the script, is leading the fight to discredit the project. His Web site, stop​kennedys​mears​.com, features a 13-minute video with complaints about historical inaccuracies from, among others, former Kennedy aide Ted Sorenson, who helped burnish JFK’s unjustified reputation as a deep thinker by ghosting the Pulitzer-winning Profiles in Courage.

The screenwriter, Stephen Kronish, insists that he’s “not out to destroy the sacred cow” of the JFK presidency. Too bad: In an age when Americans still periodically swoon for imperial presidents, a little sacred-cow tipping would be a public service.

Greenwald carps that the script “just makes stuff up, like the scene where Kennedy says he has to [have sex] every night or he’ll go crazy.”

Actually, what Kennedy said, to British Prime Minister Harold Macmillan, was “If I don’t have a woman for three days, I get terrible headaches.” (That’s from Richard Reeves’ highly regarded President Kennedy: Profile of Power, p. 290, for anyone keeping score at home.) The scene’s not strictly accurate, but it’s hardly “made up.”

I haven’t read the script, but any sentient adult with an interest in history has known for years that Jack Kennedy had a sexual appetite to rival that of Motley Crue on world tour. Surnow’s hardly guilty of cheap moralism for pointing this out. Given that JFK’s activities periodically separated him from the Secret Service and the aide carrying the nuclear football — and that the president shared a mistress with Chicago mob boss Sam Giancana — it’s hard to argue that no issues of public concern were involved.

More troubling were Kennedy’s routine abuses of power. His attorney general, brother Bobby, ordered wiretaps on New York Times and Newsweek reporters, along with various congressmen and steel executives who’d had the nerve to raise prices.

At JFK’s instigation in 1961, the Internal Revenue Service set up a “strike force” aimed at groups opposing the administration. Nixon’s defenders had half a point when they complained that the sainted Jack had gotten away with the sort of abuses that brought Nixon’s own downfall.

Kennedy’s charm and vigor, and the tragic circumstances of his death, have made it hard to see the man clearly. A 1968 study on “juvenile idealization of the president” quoted a Houston mother: “When my little girl came out of school she told me someone killed the president, and her thoughts were — since the president was dead, where would we get our food and clothes from?” But “juvenile idealization” isn’t limited to juveniles.

Presidential biographer James MacGregor Burns, a Kennedy fan, wrote that “the stronger we make the Presidency, the more we strengthen democratic procedures.” Even today, far too many pundits and historians seem to get a Chris Matthews-style “thrill up [their] leg” when they contemplate “heroic” presidential activism.

This is an unhealthy phenomenon in a democracy. When we invest such audacious hopes in the presidency, we tend to cede vast powers as well. And when we go looking for heroes among professional politicians, we deserve all the disappointment we usually get.

It’s well past time Americans got beyond the romance of Camelot.