According to Reagan's 4 conditions for military intervention that he listed in his autobiography, he would be on Rand Paul's side in the fight against intervention. Obama's plan for an "unbelievably small" attack that makes Assad eat his Cheerios with a fork doesn't meet any of the conditions. All Presidents should refer to these often when they contemplate military action (h/t Newt):
1. The United States should not commit its forces to military action overseas unless the cause is vital to our national interest.
2. If the decision is made to commit our forces to combat abroad, it must be done with the clear intent and support needed to win. It should not be a halfway or tentative commitment, and there must be clearly defined and realistic objectives.
3. Before we commit our troops to combat, there must be reasonable assurance that the cause we are fighting for and the actions we take will have the support of the American people and Congress. (We all felt that the Vietnam War had turned into such a tragedy because military action had been undertaken without sufficient assurances that the American people were behind it.)
4. Even after all these other combat tests are met, our troops should be committed to combat abroad only as a last resort, when no other choice is available. (Ronald Reagan: An American Life, 466)