Dems are pouncing on Mitt Romney’s appearance on NBC this morning, in which he said that questions about Wall Street excess are driven by “envy,” and suggested that we should only debate inequality in “quiet rooms.”

Obama adviser David Axelrod emails a response that’s short, but interesting in what it portends about the general election:

Not a gaffe. It’s what he believes. Last week he said “productivity equals income.”

But the point is, it hasn’t for the typical American worker over the last three decades, and, particularly, over the last decade.

This is the central challenge of our time, and he doesn’t get it.

If the Obama campaign intends to frame the campaign around the idea that inequality and economic unfairness are the “central challenge of our time,” and to base the case against Romney on what unregulated capitalism has wrought, this could be epic. The battle will be fought largely over two competing visions of capitalism itself, and of government’s proper role in regulating it, at a time when the public has been more focused on issues of inequality and economic injustice than at any time in recent memory.

Relatedly, the pro-Gingrich Super PAC has just released its long documentary about Romney’s Bain years, and it’s very hard hitting stuff. Remarkably, much of the footage in this video — it features Bain layoff victims talking about how devastated their communities were by Romney’s “job creating” investments — would be perfectly at home in Dem attack ads.

As I said yesterday, Romney’s claim that his brand of capitalism represents the American way has now been panned by bipartisan agreement — a very clear sign of which way the winds of populism are blowing in American politics right now. Indeed, even Frank Luntz is advising Republicans to stop defending “capitalism,” and is telling them to defend “economic freedom” instead.