Hawkish U.S. Sens. John McCain, Lindsey Graham and Joe Lieberman have called for direct U.S. military involvement in Syria, but countervailing voices say: Cool it.

Charles Krauthammer’s is one of those voices.

“I think Obama is right on this and McCain is wrong,” Krauthammer said. “I think this is not Libya. Libya is an oil well with a long beach and a primitive army. Syria has a serious air force, a serious army, and this would be a serious war.”

Krauthammer proposed reviving “the Reagan Doctrine,” a covert strategy of supporting insurgencies. Krauthammer first coined the term in 1985.

“I think what we should adopt is the Reagan Doctrine, the way he combated the expansion of Soviet influence in Nicaragua, Afghanistan, Angola. You support the insurgency. You don’t put Americans on the ground or in the air,” he said. “And why we aren’t arming and training and helping the insurgents in Turkey, you know, the ones who defected into Turkey out of Syria, I do not understand.”

Krauthammer is right — and not the only bright mind — to point to the Reagan Doctrine, but he misses an important point: The president’s actions in Libya — successful though they might have been — established a precedent of some kind of military intervention even when the United States doesn’t have a compelling national security interest in a conflict. In a press release, Sen. Jim Webb observed that problem with the Libyan model and, like Krauthammer, urged restraint when it comes to Syria:

“When people are talking about the need for leadership, we need to have a little sense of history. Leadership is not always taking precipitant action when the emotions are going. It is in achieving results that will bring about long-term objectives,” said Senator Webb, who served as Assistant Secretary of Defense and as Secretary of the Navy in the Reagan administration. “Probably the greatest strategic victory in our lifetime was the Cold War. That was a conscious, decades-long, application of strategy with the right signals with respect to our national security apparatus.”

Senator Webb reiterated his concerns about the precedent set by the President’s unilateral decision to use force in Libya, where historical definitions of national security interest were not clearly met. “I have a great deal of concern when you look at the Libya model where the basic justification has been humanitarian assistance, which is very vague and is not under the historical precepts that we have otherwise used,” said Senator Webb.

Right now, the calmer voices have Obama’s ear — but will that continue to be the case as the crisis heats up? We’ll see. Syrian army attacks continue in the northwest city of Idlib and U.N.-Arab League envoy Kofi Annan is in Syria to ask for the cessation of all violence from President Bashar al-Assad. You can guess what Assad’s reply was.