Obama's 'prevarication has damaged US'

The United States has reversed its opposition to a no-fly zone over Libya and is now indicating that it is lobbying for more far-reaching measures on the ground. As Muammer Gaddafi's forces seek to retake Benghazi, James Blitz, diplomatic editor, discusses with the FT's Richard Edgar, what has changed President Obama's mind, what damage the delay has done, and what action can now be expected on Libya.