On NBC’s Meet the Press back in April 2013, Senator John McCain said that we should arm the Syrian rebels but not put US troops on the ground:
Well, as I said, a safe zone of arming the rebels, making sure that we help with the refugees. And be prepared with an international force to go in and secure these stocks of chemical and perhaps biological weapons. … But the worst thing the United States could do right now is put boots on the ground on Syria. That would turn the people against us.
Now, in light of recent news about chemical warfare, the NYTimes has called Secretary of State John Kerry the chief advocate for US intervention in Syria:
We know that after a decade of conflict, the American people are tired of war — believe me, I am, too. But fatigue does not absolve us of our responsibility. Just longing for peace does not necessarily bring it about. And history would judge us all extraordinarily harshly if we turned a blind eye to a dictator’s wanton use of weapons of mass destruction against all warnings, against all common understanding of decency.
Everything is controversial here, history included. But this concise piece from Fareed Zakaria back in June 2013 seems to offer some historical insights into the current situation: