Ezra Klein:

“I reject the notion that they key to future prosperity is the top marginal tax rate,” [Orszag] shot back. It’s a good line, and conceptually, an important statement of what separates the Obama administration’s economic philosophy from the Bush administration’s. If you think the drivers of growth are in the top one percent, and that top one percent is exquisitely sensitive to small changes in marginal tax rates, your policy proposals will be rather different than if you think prosperity and security for the broad middle is a more sustainable approach to growth.

I really like this framing.