So what was 9/11 all about?

According to Robert A. Pape's "database of every suicide bombing and attack around the globe from 1980 through 2003 - 315 in all", which "excludes attacks authorized by a national government",

The data show that there is far less of a connection between suicide terrorism and religious fundamentalism than most people think.

The leading instigators of suicide attacks are 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).

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What nearly all suicide terrorist attacks actually have in common is a specific secular and strategic goal: to compel modern democracies to withdraw military forces from territory that the terrorists consider to be their homeland. Religion is often used as a tool by terrorist organizations in recruiting and in seeking aid from abroad, but is rarely the root cause.

Three general patterns in the data support these conclusions.

• First, nearly all suicide terrorist attacks - 301 of the 315 in the period I studied - took place as part of organized political or military campaigns.
• Second, democracies are uniquely vulnerable to suicide terrorists; America, France, India, Israel, Russia, Sri Lanka and Turkey have been the targets of almost every suicide attack of the past two decades.
• Third, suicide terrorist campaigns are directed toward a strategic objective: From Lebanon to Israel to Sri Lanka to Kashmir to Chechnya, the sponsors of every campaign - 18 organizations in all - are seeking to establish or maintain political self-determination.