If POTUS Caves on Tax Cuts, Why not All of It?

Economist Mark Thoma puts it succinctly:

Obama made it seem as though this is an issue where he won't compromise, but instead of holding the line and hammering Republicans day in and day out to make it clear who is standing in the way of extending middle class tax cuts, he caves. Why should we trust the administration to negotiate on issues such as Social Security when it can't even win this political battle? When Axelrod says "the president's commitments haven't changed," shouldn't he add "though we have to deal with the world as we find it"? Saying the president's commitments haven't changed yet is not a promise they won't change in the future, and Obama's history suggests they very well might.