What is the color of the Iraqi insurgency?

And by color I mean nature, character, etc., i.e. who is attacking who?

Does anyone know what percentages the near daily insurgent attacks break down into? Are radical Sunni elements attacking Shi’ite populations more than vice versa, less?

Are either radical populations attacking the U.S. and its allies more often than the other? What are the percentages of attacks against other entities? Is anyone keeping track? Inspired by this event.

Thanks for any information.

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