When word leaked that Exxon CEO Rex Tillerson, a holder of the Order of Friendship award in Putin’s Russia, was Donald Trump’s choice for secretary of state, John McCain had this thoughtful response: “Vladimir Putin is a thug, a bully, and a murderer and anybody else who describes him as anything else is lying.” Yet, Putin is something else, the leader of the largest nation on earth, a great power with enough nuclear weapons to wipe the United States off the face of the earth. And we have to deal with him. McCain was echoed by the senior Democrat on...