The abrupt about-face on Syria, the global humiliation resulting from the U.S. government shutdown, the continuing fallout from revelations about National Security Agency activities, strong statements emanating from Riyadh that Saudi Arabia is re-evaluating its relationship with the United States—all of these have fed into a narrative that the United States is losing the ability to set the global agenda. The perception that President Barack Obama has been weakened led Forbes magazine to drop him to the No. 2 spot on the list of the world’s most powerful people, with Russia’s Vladimir Putin leapfrogging him to take the top position […]