If Mr. Trump gets precisely the policies he says he wants, then the economy will suffer a recession.

There is plenty of blame to go around for the U.S. housing bubble, but not much of it belongs to Fannie Mae and Freddie Mac. The two giant housing-finance institutions made many mistakes over the decades, some of them real whoppers, but causing house prices to soar and then crater during the past decade weren't among them.

A housing renaissance has begun. This may be hard to believe after the dizzying, six-year-long crash in home sales, construction and house prices. But housing turned the corner last year, and it will take off in 2013.

Our biggest challenge is to eliminate the popular perception that economists don't have anything useful to say.

Indeed, the FHA was born out of the Great Depression, which was also caused in significant part by a foreclosure crisis. Mortgages in the early 1930s were mostly three- to five-year 'bullet' loans, which did not amortize and were due in full at maturity.

The Bush tax cuts should be extended permanently for families with annual incomes of less than $250,000 and should be phased out slowly for those making more than that. Raising taxes on anyone now, when the economic recovery is so fragile, would be a mistake.

The most important point is, in a time of crisis, there is no way out but for the government to be bold and aggressive.