Because Obama made the decision, they know they're against it. But it took most of them a day or two to settle on exactly why, in part because so many of them had called for intervention before Obama pulled the trigger.
Newt Gingrich. Two weeks ago, the former House speaker and possible presidential candidate denounced Obama for not intervening forcefully against Kadafi.
"This is a moment to get rid of [Kadafi]," he urged. "Do it. Get it over with."
Then Obama intervened in Libya. Was Gingrich pleased?
"It is impossible to make sense of the standard for intervention in Libya except opportunism and news media publicity," Gingrich said Sunday. "Iran and North Korea are vastly bigger threats…. There are a lot of bad dictators doing bad things."
That sounded like a flip-flop, so I asked Gingrich what he meant. He responded with an e-mail: "The only rational purpose for an intervention is to replace Kadafi. That is what the president called for on March 3, and after that statement anything less is a defeat for the United States."
Like Gingrich, most of the current potential presidential candidates suddenly sound a lot like a Republican president they don't often praise: George W. Bush.
Their main purpose, of course, is to portray the Democratic incumbent as weak and indecisive. But along the way, they have begun to sketch their own visions of foreign policy leadership, and they sound a lot like the man who left the White House for Texas two years ago.
Like Bush, they favor using U.S. military power to topple Middle Eastern dictators. Like Bush, they don't see much need for blessings from the United Nations Security Council or any other international body. And like Bush, they think foreign policy decisions should be quick and clear, not drawn out and complicated — or, to use their newest term of derogation, "nuanced."
Most of the would-be candidates applaud the principle of intervening against Kadafi, since they called for it before Obama's action. But their applause is much quieter than their complaints — that the president shouldn't have waited so long and that he sacrificed U.S. sovereignty by waiting for endorsements from the U.N. and others.
"I support military action in Libya," said former Massachusetts Gov. Mitt Romney — but then he excoriated the specifics of Obama's policy.
"He calls for the removal of Moammar Kadafi but then conditions our action on the directions we get from the Arab League and United Nations," Romney said.
And then, the core of his critique of Obama. "He's tentative, indecisive, timid and nuanced," Romney said. (As George W. Bush once told a surprised British journalist: "I don't do nuance.")
Former Minnesota Gov. Tim Pawlenty suggested that Obama has allowed France's Nicolas Sarkozy to usurp his role as leader of the free world.
Former Alaska Gov. Sarah Palin, on a speaking tour in India, demurred from offering a full-scale critique of Obama's policy but promised that if she were president, there would certainly be "less dithering."
In the vast Republican presidential field, there were only two prominent dissidents who questioned whether intervention in Libya was wise: Texas Rep. Ron Paul, a libertarian who has generally opposed foreign entanglements, and Mississippi Gov. Haley Barbour, who seemed to reflect the more cautious, "realist" approach of the Republican establishment that led the party before Bush.
"Whenever our men and women are involved in military action, every American stands with them," Barbour told reporters this week. "This is not the time to critique what the administration has done or will do." Before the intervention, Barbour said he was skeptical. "I don't think it's our mission to make Libya look like Luxembourg," he said last week.
If Obama gets lucky and the military campaign results in Kadafi's fall, Republicans will still fault him for timidity and indecision (not to mention nuance), but their criticism won't have much sting. If Kadafi clings to power, the hawkish Republicans have already staked out their critique: The dictator wouldn't be there if Obama had listened to them.
But by implicitly embracing the legacy of Bush, this new generation of Republican hawks is taking a political risk. Telling war-weary Americans that they favor military interventions against foreign dictators may attract the votes of hawkish conservatives in Republican primaries, but it doesn't look like a winning pitch in a general election campaign.
Both parties are divided over the military campaign in Libya, but the leading voices in both parties are interventionists. One party favors intervention reluctantly, seeks international support and tries to narrow its goals — often to its own discomfort. The other favors intervention more enthusiastically, disdains international support and is quicker to endorse the goal of regime change.
One party sees nuance as a virtue, the other as a vice. American voters may not embrace nuance at home. But given the choice, they may prefer a dose of it in their foreign policy.