WASHINGTON (AP) " President Donald Trump's criticism of NATO allies and his friendly overtures to Russian President Vladimir Putin are stirring questions at home and abroad about Trump's commitment to the Atlantic alliance.

The alliance has been a pillar of U.S. security policy for more than half a century, but Trump's combative attitude is fueling speculation that a reordering of U.S. forces in Europe might be in the cards.

Trump gathers Wednesday with NATO leaders in Brussels. They will consider increasing forces capable of reacting quickly in a European crisis, but overshadowing that are tensions generated by Trump's view that the Europeans are slackers leaning unfairly on the U.S. military.

Trump will then sit down in Finland with Putin. He said Tuesday that "may be the easiest" of his meetings in Europe.