Perhaps I'm being too machiavellian, but it occurs to me that maybe the president wanted it leaked. It's only a contingency plan, but leaking it now may have been a way to send a timely message to the "axis" et al.
Sure some Dems are capable of it for nefarious reasons, but note that the president's popularity numbers are still up.
So liberals are sneering, the Iranian government calls him a maniac, and a liberal rag in the UK doesn't like it? Tony Blair is with us, but some members of his party like to grandstand? So?