At a minimum, both Romer and Geithner could have served under Gerald Ford or George H. W. Bush. But they may be more pro-growth than that. Romer’s study of the damage of tax hikes on the economy and her emphasis on investment are right on target. In a New York Times story, a former Treasury colleague of Geithner’s says, “he’s no liberal.” As for Summers, while he has been mau-maued by Democratic feminists and some of the unions, he is a tough, clear-headed thinker who has for years tried to merge Keynesian and supply-side policies. No mean feat.

Now here’s the rub: all this talk about a $700 billion stimulus package. I hate to be the one to pull the plug, but government cannot spend our way into prosperity. The wish list of Democratic spending initiatives includes short-term tax rebates, massive new transportation bills, even more education money, exotic green-technology spending, a big-government embrace of health care, and heaps of cash for UAW-Detroit carmakers. None of that will stimulate economic growth.

Economist Paul Hoffmeister has it right: We need to invigorate incentives to produce and invest. Let me take it even further. We need to revive the dormant animal spirits, which have been beaten down by a brutal bear market in stocks, the ongoing housing slump, and all the myriad blockages to credit availability. A bunch of new spending won’t do the trick. Lower tax rates will.

Government policy must make it clear that new successes will be handsomely rewarded. This will be Obama’s greatest challenge. While he may not raise taxes in 2009 -- a good thing -- he hasn’t yet come up with a new bolt of electricity that will hardwire the serious risk-taking that lies at the heart of free-market capitalism. Right now, the missing electric bolt is lower tax rates and greater rewards for new risk investment by investors, successful earners, and business.

On the plus side, however, Mr. Obama talks optimistically. That’s good. He says he’s hopeful about our future. And he says he is confident that American spirits will be resilient in this difficult time. That’s Reagansesque, Kennedyesque, and FDResque. But while FDR’s big-spending and regulating prevented economic recovery, Kennedy and Reagan opted for across-the-board supply-side tax-rate reductions to get America moving again.