To justify its $5 trillion figure — the estimated tax loss over a decade — the Obama campaign had to cherry-pick Romney’s proposal and the TPC analysis. It had to ignore any revenue raised by reducing tax breaks and assume that, faced with a conflict between the rich and the middle class, Romney would automatically side with the rich — as opposed to shielding the middle class from any tax increase. On Wednesday, Romney promised to protect the middle class.

The TPC report was widely interpreted as saying Romney would have to raise taxes on the middle class. It didn’t, says the TPC’s Howard Gleckman. It simply pointed out that he couldn’t keep all “his ambitious campaign promises.” He’d have to make choices and modifications. So what else is new?

Politicians exaggerate and simplify. They make more promises than can be kept. They take inconsistent positions. Romney is guilty of this, but so is Obama. Obama says he favors tax reform but would also raise the top income tax rate to 39.6 percent from 35 percent. That’s the opposite of what most economists consider reform: cutting rates and broadening the tax base. Similarly, Obama has said he would maintain a strong military while rapidly reducing defense spending.