Sen. Van Hollen: Trump's maximum pressure campaign 'brought us to the brink' against Iran
02:13Senator Chris Van Hollen (D-MD) joins Andrea Mitchell in the wake of new revelations that US sources say that the Ukrainian plane was shot down by Iranian missiles, a situation he calls a 'humanitarian crisis' that should allow for exceptions to Trump's proposed sanctions. He also tells Andrea that he believes we are 'closer to war with Iran" than ever before.'