Tim Pawlenty has staked out the maximal hawkish position within the Republican primary field. At the same time, he and every Republican candidate must maintain maximal Ronald Reagan fealty. Jeffrey Goldberg interviews Pawlenty and watches the brain circuits fry:

Lately, some conservatives have taken to praising President Ronald Reagan’s decision to withdraw from Lebanon after the fatal Marine-barracks bombing in 1983. ...
I asked Pawlenty if he thought Reagan’s decision to withdraw from Lebanon was wrong. He went silent.
“Am I putting you in the uniquely uncomfortable position of criticizing Ronald Reagan?” I asked.
“I guess I would go back and say that my view, without referencing a particular president, is that once the United States commits to a mission, it’s really important that we prevail. Because when you don’t, it diminishes the respect and credibility and awe that other people view the United States with. And our goal here is to avoid as many future conflicts as possible by having our relative position be so strong and so unquestioned and so certain that nobody dare challenge us.”

I believe the correct answer is: Reagan withdrew the Marines from Lebanon in order to demonstrate the importance of American resolve.