Open this photo in gallery:U.S. President Donald Trump speaks with Prime Minister Mark Carney, at a working lunch with leaders of G7 and the Middle East in Evian-les-Bains, France, on June 16.Evelyn Hockstein/The Associated PressSave for laterJohn Rapley is a contributing columnist for The Globe and Mail. He is an author and academic whose books include Why Empires Fall and Twilight of the Money Gods.When it comes to negotiating deals with U.S. President Donald Trump, the saying in Washington is that reaching an agreement with him doesn’t buy you peace, it only buys you time. Any pact will be subject…