Trump questions NATO allies' will for collective defense while casting doubt on U.S.' own treaty commitment

President Trump suggested Thursday that members of the U.S.-led NATO transatlantic military alliance would not come to the aid of the U.S., should America come under attack. NATO members are bound to back each other militarily in the face of any aggression under the collective defense clause in the alliance's founding treaty.

"Do you think they're going to come and protect us? Hmm. They're supposed to. I'm not so sure," Mr. Trump said as he addressed reporters at the Oval Office. 

He said in the same conversation that he would breach that treaty and only send the U.S. military to defend NATO allies that contribute what he deems to be a fair share of their national GDPs to their defense budgets.