Why do Republicans drive leftists so crazy these days? Liberal Democrats are beginning to sound like rowdy students on spring break, shrieking and exhibiting themselves on camera.

Consider some of the recent rabid outbursts by once sober, old-guard politicians. West Virginia Sen. Jay Rockefeller insists that the world would be better off if Saddam were still running Iraq. Crotchety Congressman John Murtha, of Pennsylvania, rushed to announce that our Marines were guilty of killing Iraqis in "cold blood" before they were tried. Illinois Sen. Richard Durbin has compared our interrogators at Guantanamo Bay to Nazis, while Massachusetts Sen. John Kerry said our soldiers have "terrorized" Iraqi women and children.

Then there is the constant anger from Democratic ex-presidents. It used to be that out-of-office chief executives kept relatively hushed. Presidents Ford and Bush Sr. — both voted out of office — did not bray when President Clinton had his trials, personal and otherwise.

Not so now with Presidents Carter and Clinton. They repeatedly harp about the sins of the current administration. By now, everyone has seen clips of Clinton losing his temper (complete with finger-wagging) and lashing out at the "right-wingers" on TV. He lectures on political extremism, even as one of his wife's staff members slandered John McCain by saying he broke under torture while a POW in Hanoi. And even at 82, Jimmy Carter almost daily carps over Bush's foreign policy.

Do not forget the unhinged billionaire leftist philanthropists. Ted Turner said he resented President Bush asking Americans, after 9/11, to take sides in our war against Islamic terrorists. George Soros claimed that President Bush improved on Nazi propaganda methods.

The frustration with Bush & Co. has driven a few in the media almost to the point of clinical madness. In 2004, a clueless Dan Rather imploded by airing clearly forged memos that called into question Bush's National Guard service — with the result that he was eased out by an embarrassed CBS News. More recently, Keith Olbermann, the foaming news head on the struggling cable channel MSNBC, keeps his ratings low with uncontrollable rants about Secretary of Defense Donald Rumsfeld pushing a "new fascism."

On college campuses, the old leftist intolerance of unwelcome free speech is back with a fury. A guest spokesman for the Minutemen immigration reform group was shouted down at a recent Columbia University lecture. Earlier, Harvard's liberal president Larry Summers was forced out, after timidly questioning academic orthodoxy about the role of women in science and engineering.

What sends liberal criticism over the edge into pathological hysteria?

Is it that George Bush is a polarizing figure, not just in terms of his Iraq policy, but also because of his Christian Texan demeanor?

Or is the current left-wing savagery also a legacy of the tribal 1960s, when out-of-power protestors felt that expressions of speaking bluntly, even crudely, were at least preferable to "artificial" cultural restraint? Why should graying veterans of the barricades, then, remain "polite" when their country's less sophisticated red-state yokels are taking it in the wrong direction?

The Democrats have not elected congressional majorities in 12 years, and they've occupied the White House in only eight of the last 26 years. The left's current unruliness seems a way of scapegoating others for a more elemental frustration — that they can't gain a national majority based on their core beliefs. More entitlements, higher taxes to pay for them, gay marriage, de facto quotas in affirmative action, open borders, abortion on demand, and radical secularism — these liberal issues don't tend to resonate with most Americans.

To compensate, leftist pundits, billionaire philanthropists and politicians, from current officeholders to ex-presidents, work to ensure that isolated moments of Republican ineptness (George Bush strutting on a carrier deck in his flight suit) and wrongdoing (repulsive e-mails from a perverted Congressman Mark Foley) blare out as the only issues of the day. This distracting drumbeat, not their own agenda, is the only strategy for success in the next election.

True, reactionaries in the 1990s expressed a Neanderthal hatred of Bill Clinton. But now shouting leftists have lowered the bar. The danger, of course, is that by emulating the rhetoric of a Cindy Sheehan or Michael Moore, the feral Democrats — when they come back into power again as tamed leaders who must govern — will have created Frankensteins. And, as we know, such monsters always turn on their creators.

Victor Davis Hanson is a classicist and historian at the Hoover Institution at Stanford University. Reach him at author@victorhanson.com.