The White House has been fighting to prevent the disastrous rollout of the health care law from defining President Obama's second term. While that struggle continues, another story is unfolding this week that could shape this president's legacy.
Diplomats from the U.S. and other countries are going to meet for a second round of negotiations on Iran's nuclear program, and a breakthrough there could shape history's view of Obama.
Presidential second terms are often defined by foreign rather than domestic affairs, for better or worse.