Watching the evolution of economic discussion in Washington over the past couple of years has been a disheartening experience. Month by month, the discourse has gotten more primitive; with stunning speed, the lessons of the 2008 financial crisis have been forgotten, and the very ideas that got us into the crisis — regulation is always bad, what’s good for the bankers is good for America, tax cuts are the universal elixir — have regained their hold.

And now trickle-down economics — specifically, the idea that anything that increases corporate profits is good for the economy — is making a comeback.

On the face of it, this seems bizarre. Over the last two years profits have soared while unemployment has remained disastrously high. Why should anyone believe that handing even more money to corporations, no strings attached, would lead to faster job creation?

Nonetheless, trickle-down is clearly on the ascendant — and even some Democrats are buying into it. What am I talking about? Consider first the arguments Republicans are using to defend outrageous tax loopholes. How can people simultaneously demand savage cuts in Medicare and Medicaid and defend special tax breaks favoring hedge fund managers and owners of corporate jets?