The Navy is adding to the assets, making it possible for either President Obama to strike after the election, or for the next president to strike Iran soon after taking office:
The U.S. is sending another carrier task force to the Persian Gulf, and the ships are heading out four months early and will stay at sea for eight months instead of four. There are already two carrier task forces in the Gulf area, and for a short while there will be three when the third task force arrives in five months.
So from December 2012 to March 2013, we'll have three carriers near Iran. Somebody in the White House will have options.