Looking ahead to what the dynamic between them will be now, aides to the president and new speaker point to their collaboration on getting trade fast-track through Congress last summer as a model. People in both offices note that the two leaders helped produce a bill with bipartisan support and tea-party opposition that the president eagerly signed. They’re a lot less eager to talk about what happened behind-the-scenes to get there: significant collaboration between the president's staff in the West Wing and Ryan's staff on the Ways and Means Committee, along with several direct phone calls the White House still...