HuffPost Entertainment Donald J. Trump was not in his natural environment at the NATO summit.

MSNBC President Donald Trump engaged in some sharp-elbowed diplomacy Thursday at the NATO summit — literally.

Yahoo News Donald J. Trump called NATO "obsolete" on the campaign trail — now he's attending his first NATO summit: https://yhoo.it/2r0al2c

HuffPost Politics After calling NATO "obsolete" on the campaign trail and changing his position on the military alliance several times since, President Donald Trump attends his first NATO summit. He'll deliver remarks and unveil a Sept. 11 memorial alongside German Ch Read more ... ancellor Angela Merkel, who will present a Berlin Wall memorial.

CNN Politics Though President Donald J. Trump has backtracked on his claims that NATO is "obsolete", NATO allies in Europe remain concerned and want him to make a full commitment to the collective defense principle of NATO treaty.

Newsweek President Donald Trump’s supposedly short attention span has NATO reworking its usual summit discussion format.

NBC News President Trump agreed to attend the summit in Brussels after having repeatedly criticized the alliance. He called it "obsolete" as late as last month.

Reuters Ukraine won promises of continued support at a NATO summit on Saturday but the prospect of Kiev's eventual membership of the U.S.-led military alliance seemed as distant as ever as the West seeks a tentative rapprochement with Russia.

Newsweek Europe Why is the NATO summit so important?

CNN Politics President Obama departs for a high-stakes NATO summit in Poland, marking what's likely to be his final presidential trip to Europe as the continent faces a moment of historic uncertainty.