From Winds of Change [linkfrom Instapundit]:
"First of all, claims that this has to do with the Russian military presence in Chechnya completely misunderstand the situation. The problem with Chechnya, more or less, is that the Russians tried to surrender after their failure to bring the rebellious republic back into the fold in the first Chechen war and it didn't work. The country was taken over by a mixture of international terrorist organizations, Wahhabi theocrats, drug cartels, and other criminal organizations that subsided more or less on generous funding from Saudi Arabia and other Gulf states. This funding helped the Wahhabis to finalize control over the institutional infrastructure of the de facto independent state and led for calls for the imposition of sha'riah even though most Chechens (and Caucasus Muslims in general) are Sufis. The al-Qaeda presence in Chechnya was headed up by bin Laden's protege Amir ibn al-Khattab, a Saudi national who had previously assisted Islamic fighters in the Tajik Civil War and the Armenia-Azerbaijan War over Nagorno-Karabakh. In 1999, Khattab and his 'Islamic International Brigade' used Chechnya as a base from which to invade the neighboring Russian republic of Dagestan (summarized here by GlobalSecurity) as part of a long-term al-Qaeda strategy to export the Chechen political culture to the rest of the Caucasus. That failed invasion of Dagestan marks the proper beginning of the current fighting in Chechnya."