BRUSSELS, BELGIUM - MAY 25:  US President, Donald Trump and British Prime Minister, Theresa May are pictured ahead of a photo opportunity of leaders as they arrive for a NATO summit meeting on May 25, 2017 in Brussels, Belgium. The North Atlantic Treaty Organisation (NATO) is made up of 28 countries. This year's summit is held at their new headquarters in Brussels.  The US President Donald Trump will meet other leaders to discuss NATO taking a greater role in the fight against ISIS.  (Photo by Dan Kitwood/Getty Images)