It isn’t about ‘fulfilling his promise’, it’s about letting them go.
Via Daily Mail:
The Obama administration is running out of time and options to close the Guantanamo Bay detention center in Cuba, so officials are scrambling to release as many prisoners as possible and considering novel legal strategies that include allowing some men to strike plea deals by video-teleconference and sending others to foreign countries to be prosecuted.
But it looks to be little, too late to close the prison before President Barack Obama leaves office in January, denying him the chance to fulfill a campaign pledge.
There’s the difficulty in transferring prisoners from the U.S. base in Cuba, questions about the legality of plea deals and solid opposition in Congress to anything that might help Obama achieve that promise.