Sen. John McCain (R-Ariz.) took a jab at President Trump on Saturday after threatening to impose new tariffs on Canada and pulling his endorsement of a joint communique signed with other Group of Seven (G-7) members at this weekend's summit. “To our allies: bipartisan majorities of Americans remain pro-free trade, pro-globalization & supportive of alliances based on 70 years of shared values,” McCain tweeted late Saturday. “Americans stand with you, even if our president doesn’t,” the senator added. Ect...