Historians of propaganda are familiar with the concept of the Big Lie, a claim so extreme that many people end up accepting it because they can’t believe that authority figures would make up something so at odds with reality.

It often seems to me that we need a term to describe a somewhat similar phenomenon in policy debates, which we might call the Big Grift. What I mean are policy proposals so corrupt, so obviously designed to benefit an undeserving few at everyone else’s expense, that many voters balk at the notion that seemingly respectable politicians actually advocate such things.

A case in point is the current demand by House Republicans that funding for Israel in this moment of crisis be tied to budget cuts that would undermine the ability of the Internal Revenue Service to crack down on wealthy tax cheats. This should be a major scandal, but my suspicion is that many voters just won’t accept the idea that G.O.P. leaders would do something so cartoonishly villainous.

Some history: Way back in 2001, in the aftermath of Sept. 11, House Republicans passed a bill responding to the emergency by … cutting corporate taxes. At the time, my sources told me that when political consultants tried to describe the bill to focus groups of voters, they refused to believe that the legislation was being described accurately.