If the U.S. had had a presence [in Iraq], we would have had more leverage over how Maliki conducted his affairs, you would have had a more stable region, but also a place where you could conduct operations against other threats in the region.
This kind of stuff is crazy. We had troops in Iraq for a decade. During that time, which spanned two different US presidents, we had virtually no success at getting Nouri al-Maliki to form an inclusive government that didn't gratuitously piss off Sunnis as a routine element of policy. Hell, Maliki didn't even take advantage of the Sunni Awakening, which was the best opportunity ever likely to come along to forge a Sunni-Shia alliance, to change his stripes. If that didn't do the trick, along with a hundred thousand American troops and near-daily calls with President Bush, what possible hope is there that a small residual force would have had any leverage at all?
This is the kind of thing that drives me batty. I get that Republicans want to criticize Obama. That's pretty much the job description of the opposition party. I also get that the default Republican response to any national security initiative from President Obama is a reflexive "Do more." That's how they keep their hawkish reputation intact. But this kind of thing just flatly makes no sense. Does Rubio really believe this nonsense, or does he just spout it on Fox News because he figures it sounds plausible?