Russia hit by Islamic suicide bombers?

I'd have used the headline "Russia hit by radical Islamic suicide bombers?" except it seemed redundant.

No group immediately took responsibility for the blasts but suspicion is likely to fall on groups from Russia's North Caucasus, where the Kremlin is fighting a growing Islamist insurgency.
(Reuters)

If I remember my American progressive talking points correctly, the Russians should cut the Caucasus loose and forget about it.  You can't fight an insurgency.