Analysis: The prime minister came out of his meeting with the American president this week glowing, and said it was one of their best ever; officials in the White House were a bit more even-tempered.

Analysis: The mega-attack in Paris changes, in the short run, the nature of the international debate over Syria's future. The West wanted to have it both ways: Destroy the Islamic State and topple Assad's regime. Now, it must reconsider its list of priorities.