Putin's Closing Window on Ukraine

President Putin may "see a closing window, politically and militarily, to take back Ukraine," says Nonresident Senior Fellow in Foreign Policy Mitchel Wallerstein with Michael Holmes on CNN.

"He's made no secret of the fact that he wants to reestablish as much as the Soviet empire as possible. And with Ukraine drifting towards the West, he may feel that he has little time left in which to accomplish this. Particularly with the US, politically in disarray at the moment, he may see this as the ideal opportunity."