Well, wanting to withdraw troops is not the same as breaking treaties, as you well know.
Right now we have agreements with those countries that our troops should be there. Those agreements can be changed through diplomatic channels prior to bringing our forces back home. If a hypothetical President Paul thought them unconstitutional, then he should work to change them.
But the international repercussions of just yanking troops, in violation of treaty and without preamble, would be awful. It would be a profoundly Stupid Move...on that I think we can both agree.
But I also believe that Ron Paul probably knows that, understand that the ship of state takes a long time to get turned around, and wouldn't do something so profoundly stupid.