Read some of it below, the rest at the above link.
"Al Qaeda Blows It: This is a lot worse than those Danish cartoons"
"The bombing of the shrine of Imams Ali al-Hadi and Hasan al-Askari in Samarra, Iraq, one of the holiest sites in Shia Islam, has sent crowds into the streets in protest and led to reprisal attacks on dozens of Sunni mosques. So is Iraq on the verge of the long-expected sectarian conflict that will tear the country apart? Don’t count on it.
The attack was most probably perpetrated by al Qaeda, which has been trying to foment civil strife in Iraq for some time, and declared open war on the Shiites last year. They have mounted numerous provocative attacks on Shia and Kurdish targets, to no noticeable effect.
This strike was much more audacious; the (previously) golden-domed shrine is an ancient and revered structure, and the tombs within are holy both to Shiites and Sunnis, though more so to the former. The initial retaliatory attacks on Sunni mosques must have pleased Zarqawi; if taking down this site did not start the civil war, nothing would.
So the foreign fighters must have been stunned when Shiite and Sunni leaders rushed out statements saying they knew that the takfiri (i.e., those who accuse other Muslims of being infidels, a code word in this context for the foreign extremists) were behind the attack, and they would not let this act of brutality divide Iraq...."