CHICAGO - MANY Americans are mystified by the recent rise in the number and the audacity of suicide attacks in Iraq. The lull in violence after January's successful elections seemed to suggest that the march of democracy was trampling the threat of terrorism. But as electoral politics is taking root, the Iraqi insurgency and suicide terrorism are actually gaining momentum. In the past two weeks, suicide attackers have killed more than 420 Iraqis working with the United States and its allies. There were 20 such incidents in 2003, nearly 50 in 2004, and they are on pace to set a new record this year.

To make sense of this apparent contradiction, one has to understand the strategic logic of suicide terrorism. Since Muslim terrorists professing religious motives have perpetrated many of the attacks, it might seem obvious that Islamic fundamentalism is the central cause, and thus the wholesale transformation of Muslim societies into secular democracies, even at the barrel of a gun, is the obvious solution. However, the presumed connection between suicide terrorism and Islamic fundamentalism is misleading, and it may spur American policies that are likely to worsen the situation.

Over the past two years, I have compiled a database of every suicide bombing and attack around the globe from 1980 through 2003 -- 315 in all. This includes every episode in which at least one terrorist killed himself or herself while trying to kill others, but excludes attacks authorized by a national government (like those by North Korean agents against South Korea). The data show that there is far less of a connection between suicide terrorism and religious fundamentalism than most people think.

The leading instigator of suicide attacks is the Tamil Tigers in Sri Lanka, a Marxist-Leninist group whose members are from Hindu families but who are adamantly opposed to religion. This group committed 76 of the 315 incidents, more than Hamas (54) or Islamic Jihad (27). Even among Muslims, secular groups like the Kurdistan Workers' Party, the Popular Front for the Liberation of Palestine and the Al Aksa Martyr Brigades account for more than a third of suicide attacks.