WASHINGTON - The late William F. Buckley and Karl Rove have little in common, other than the Republican Party and intelligence. Buckley's politics were guided by principle; Rove's principles are guided by politics.
Yet Rove, the party establishment's money and strategy guru, is channeling Buckley, a founding father of contemporary conservatism, by trying to root out extremism from the Republican mainstream. A half-century ago Buckley sought to expunge the John Birch Society, anti-Semites and white supremacists from the party's inner circles. Today, Rove is threatening to finance primary campaigns against those he considers right-wing extremists of the type that already have cost Republicans several Senate seats.
It may be the right purpose; he's the wrong person. He can't avoid looking like an inside-the-Beltway kingmaker trying to purge populist insurgencies around the country and make some more bucks while doing it. There is a backlash.
Still, prominent Republicans with more credibility than Rove need to consider this cause. There are more than a few fringe figures who play a role in defining the party. Many of them express a vitriolic dislike of President Barack Obama that turns off possible Republican voters.
There's Steve King, the Iowa congressman who is unrelenting in his criticism of the president. One of his latest targets is the September terrorist attack in Benghazi, Libya, in which four Americans, including the U.S. ambassador, were killed.
He goes further than other critics: Benghazi, he declares, "is a lot bigger" than other scandals. It is, he says, at least 10 times bigger than Watergate or Iran-Contra combined.
He's made a name for himself with anti-immigrant rants. Last year, he said Americans should select eligible immigrants the same way they would go about picking a "good bird dog." That means choosing "the one that's the friskiest, the one that's engaged the most, and not the one that's over there sleeping in the corner." He later explained that he meant this as a compliment; he likes bird dogs.
Then there's Rep. Paul Broun of Georgia. The former physician said evolution, embryology and the Big Bang theory are "lies straight from the pit of hell." He once proposed banning Playboy magazine from military installations, which might have jeopardized the survival of the volunteer army.
Like more than a few of his colleagues on the right, his sharpest vitriol is directed at Obama. Broun boasts that he was the first to call the president "a socialist who embraces Marxist-Leninist policies." The "only constitution that Barack Obama upholds is the Soviet constitution," he charges.
Even some Republicans who aren't as far out get caught up in the fervor, particularly when it touches on Obama. This month, North Carolina Congresswoman Virginia Foxx likened those who didn't fight hard enough against the Obama administration's regulation of for-profit colleges to Germans who didn't stand up to the Nazis in the 1930s.
Texas, the biggest Republican-dominated state, is a hotbed of Obama-hating politicians. Louie Gohmert, in his fifth term in the House, asserted in November that the president ousted the dictator Moammar Qaddafi to allow al-Qaida to take over Libya.
After a 15-year hiatus, Steve Stockman returned to the House this year and wasted no time. When the president appeared at a press conference surrounded by kids after the school shooting in Newtown, Conn., Stockman compared Obama to Saddam Hussein for using children as props. He's now talking about impeaching Obama for proposing gun-control legislation.
The Senate is hardly immune. Freshman Texas Sen. Ted Cruz questioned, with no cause, whether Chuck Hagel, the nominee to be defense secretary, had taken money from terrorist states. The comment was so over the top that it was criticized by Republican Sen. John McCain, himself a Hagel critic. Far from expressing regret, Cruz seemed to revel in the controversy.
This transcends ideology. Broun has the least conservative voting record of any House Republican from Georgia, according to the latest National Journal survey of voting records. Claiming the president worships the constitution of the Soviet Union isn't a conservative position; it's a nutty one, reminiscent of the John Birchers that Buckley assailed a half-century ago.
Another freshman senator, Jeff Flake of Arizona, is every bit as conservative as Cruz and will probably vote the same way most of the time. Yet Cruz delights in vilification while Flake seeks common ground when possible.
Outside of Texas, it's the Flake persona that would offer the greatest appeal to younger or more independent voters. Many conservatives insist that the United STates remains a center-right country, where voters are receptive to the case for limited government and cultural traditionalism. The changing demographic profile of the electorate seems to undercut that case.
That's a good debate to have. However, conservatives can't compete in the argument when their party is identified with bizarre theories, bigotry and a visceral hatred of the president.
That's going to change when prominent Republicans with conservative bona fides - Rep. Paul Ryan of Wisconsin, Sen. Marco Rubio of Florida - don't just talk the talk about a broader-based party but walk the walk and reject the haters.
Albert R. Hunt is a Bloomberg View columnist.