Honestly, BO could save face by simply abiding by the vote of congress. He could say something like, "the American people have spoken and do not authorize this strike... As executive I don't have the authority...and I took this office to uphold the constitution..." or something like this
Yes, there would be a backlash from neocons and republicans who would capitalize on the "weak" and "wimp" card for political reasons, but avid Constitutionalists and libertarians would have to support this and point out that the President is doing the right thing here.
The only negative I see is it would setback any real reform because it would propagate the illusion that we are indeed a Constitutional Republic, when in reality the dictator is backed into a corner and this is the only possible move he can make.
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