SYNOPSIS:

It's Election Day, and it's your duty as a citizen to be irrational.

Let me explain. Political scientists will tell you that voting suffers from a severe "free rider" problem. Even if it's very important to you that Mr. A beat Mr. B, your individual vote is very unlikely to decide the outcome. So the sensible thing is not to bother voting. Yet if everyone acts on that logic, Mr. B — the candidate backed by corrupt special interests, which pay for his get-out-the-vote operation — sweeps into office.

In other words, even if the candidates in an election offer radically different programs, and you have a strong preference for one over the other, a narrow calculation of self-interest says that it's not worth taking the trouble to go to the polling booth. Yet democracy depends on your ability to rise above that calculation. If citizens want good government, they must do what they want others with the same concerns to do — namely, vote.

Of course, some pundits tell you that not much is at stake in this particular election, that the parties aren't really very different on the issues. I don't know what planet they are living on: in reality, the parties are further apart than they have been since the 1930's. The fact that anyone imagines otherwise is a tribute to the timidity of the Democrats, who are afraid to say what they really think, and the subterfuge of the Republicans, who show a disciplined willingness to pretend to hold positions they actually abhor.

Not only are there huge substantive differences between the parties, the background to this election means that it may determine the shape of America for decades to come.

Here's the story: In the 2000 campaign George W. Bush portrayed himself as a moderate. Toward the end the public started to catch on to this ruse, but thanks to all those Jewish retirees who voted for Pat Buchanan, the purging of minority voters from the Florida voter rolls and so on, Mr. Bush made it to the White House. Once there, his true radicalism quickly became apparent, and voters didn't like it.

But then came Sept. 11, and with it a huge surge in Mr. Bush's personal popularity. Although many pundits still talk as if he remains immensely popular, the fact is that most of that surge — about two-thirds, if you look at an average of polls — has now gone away, and the political landscape is returning to normal. Still, the Republican Party hopes that the remnants of Mr. Bush's post-terror clout can be used to regain control of the Senate — and that his radical domestic policy agenda can once again march forward, and perhaps be made irreversible.

For if we've learned one thing these past two years, it's the importance of Senate control. In his first few months in office Mr. Bush wasn't particularly popular, but Dick Cheney's vote was decisive in a 50-50 Senate — and the radical agenda rolled forward. After Sept. 11 Mr. Bush was, for a while, extremely popular, and gleeful right-wing pundits believed that he could get anything he wanted. But the Democrats had a one-vote edge in the Senate, and all of his pet domestic projects — permanent tax cuts for corporations, accelerated tax cuts for upper brackets, drilling in ANWR, hard-line judicial appointments — stalled.

This election will determine if Mr. Bush can resume the radical policy course he followed in those first few months. It will also determine the character of the nation's courts for decades; and it may greatly enlarge the Republican Party's already huge fund-raising advantage.

Now if that's what the American public wants, so be it. But it seems all too likely that this election will depend not on what the public wants but on which people bother to vote. (Or on which people are dissuaded from voting. The stories are already starting to come in; for example, someone is distributing leaflets in minority districts in Maryland telling people that they must pay parking tickets and back rent before voting.) Gallup now predicts only a 35 percent participation rate, the same as in 1998. That would be a shockingly low fraction in any year. In a year this crucial, it's appalling.

So now is the time not to be sensible. Forget those self-interested calculations. Go out there and vote — and tell everyone you know to do the same. America's future depends on your irrationality.

Originally published in The New York Times, 11.5.02