Will investors flee stocks and corporate bonds for safer assets? Such a reaction wouldn't make much sense -- after all, terrorists are not going to blow up the S.&P. 500. True, markets do sometimes react irrationally, and some foreign markets plunged after the attack. Since then, however, they have stabilized. On the whole it's just as well that our own markets have stayed closed for a few days, giving investors time to calm down; the administration was wrong to put pressure on stock markets to reopen right away. By the time the markets do reopen, the worst panic will probably be behind us.

So the direct economic impact of the attacks will probably not be that bad. And there will, potentially, be two favorable effects.

First, the driving force behind the economic slowdown has been a plunge in business investment. Now, all of a sudden, we need some new office buildings. As I've already indicated, the destruction isn't big compared with the economy, but rebuilding will generate at least some increase in business spending.

Second, the attack opens the door to some sensible recession-fighting measures. For the last few weeks there has been a heated debate among liberals over whether to advocate the classic Keynesian response to economic slowdown, a temporary burst of public spending. There were plausible economic arguments in favor of such a move, but it was questionable whether Congress could agree on how to spend the money in time to be of any use -- and there was also the certainty that conservatives would refuse to accept any such move unless it were tied to another round of irresponsible long-term tax cuts. Now it seems that we will indeed get a quick burst of public spending, however tragic the reasons.

Now for the bad news. After the attacks, I found myself wondering whether some politicians would try to exploit the horror to push their usual partisan agendas. Then I chided myself for such an uncharitable thought. But it seems you can't be too cynical; sure enough, the push is already on to sell tax breaks for corporations and a cut in the capital gains tax as a response to terrorism.