Over 520,000 lost their jobs in the last two months and retail sales collapsed, but before he even meets with his economic team, President-Elect Obama has received lots of advice lately, too much of it warning him not to attempt the agenda he ran on and frantically warning him not to believe he has the progressive mandate John McCain so conveniently defined for him.

How predictably expedient that those Very Serious Villagers who just lost and who’ve been wrong for the last eight years would now urge Obama not to do what he’s promised. But Economics Nobelist Paul Krugman, who has the tiny advantage of having been right when most others were wrong, has the perfect reply: "Ignore the trolls and go for it."

Krugman lays out a strong case that Obama’s agenda is not only smart, moral politics; it’s good economic medicine for what ails the nation’s economy:

. . . Mr. Obama ran on a platform of guaranteed health care and tax breaks for the middle class, paid for with higher taxes on the affluent. John McCain denounced his opponent as a socialist and a "redistributor," but America voted for him anyway. That’s a real mandate.

What about the argument that the economic crisis will make a progressive agenda unaffordable?

Well, there’s no question that fighting the crisis will cost a lot of money. . . .

But standard textbook economics says that it’s O.K., in fact appropriate, to run temporary deficits in the face of a depressed economy. Meanwhile, one or two years of red ink, while it would add modestly to future federal interest expenses, shouldn’t stand in the way of a health care plan that, even if quickly enacted into law, probably wouldn’t take effect until 2011.. . .

But it would be fair for the new administration to point out how conservative ideology, the belief that greed is always good, helped create this crisis. What F.D.R. said in his second inaugural address — "We have always known that heedless self-interest was bad morals; we know now that it is bad economics" — has never rung truer.

And right now happens to be one of those times when the converse is also true, and good morals are good economics. Helping the neediest in a time of crisis, through expanded health and unemployment benefits, is the morally right thing to do; it’s also a far more effective form of economic stimulus than cutting the capital gains tax. Providing aid to beleaguered state and local governments, so that they can sustain essential public services, is important for those who depend on those services; it’s also a way to avoid job losses and limit the depth of the economy’s slump.

So a serious progressive agenda — call it a new New Deal — isn’t just economically possible, it’s exactly what the economy needs.

The bottom line, then, is that Barack Obama shouldn’t listen to the people trying to scare him into being a do-nothing president. He has the political mandate; he has good economics on his side. You might say that the only thing he has to fear is fear itself. [emphasis added]

Shorter Krugman: "Ignore the Village trolls; go for a new New Deal. It’s good economics."

I like that, and I’d add one more thing. It’s also the essence of what Obama had been saying in recent speeches. I think he’s there, and so are the America people. Let’s do it.