You do not want empire? Then leave.
I'll stay, if someone else pays. If there is civil war in Iraq, Iran will be dragged in and that will be time to deal with the Persian tyrant. At that time, our oil friends will gladly pay the bill for re-engagement.
During a liquidity trap, we don't "have the money" for a plus-up in Afghanistan. "Emergency Supplemental" debt is not an option, unless team Obama want to look exactly like the fiscal pie-in-the-sky leadership of Bush-Cheney.
All options are no good.
We are fast entering the winter of discontent, and one can only hope that Paul Krugman is wrong. But, the Taylor rule, so far as I know, has not been repealed, so he can't be off by that much. Health care reform hangs on a thread. The list goes on.
The only bright spot is that the mideast peace process is in shambles. Accordingly, there is no reason for Netanyahu to bomb Iran. (What, too cynical?).