Yaroslav Trofimov writes: Before dawn in February 2006, militants sent by the precursor of today’s Islamic State sneaked into the golden-domed Shiite shrine in the Iraqi city of Samarra, disarmed the guards and rigged the building with explosives.

By most accounts, nobody died in the explosion itself, which blew off the dome and reduced the venerated mosque to rubble. But the bombing achieved its goal of baiting Iraq’s Shiite majority into a spree of retaliation against the country’s Sunnis. Thousands died in the wave of sectarian killings that began hours later, and the social fabric of Iraq was torn forever.

In this environment of sectarian strife, many Iraqi Sunnis eventually came to view Islamic State as their only, however unpalatable, protector.

That is why just a few hundred of the group’s militants were able to seize Iraq’s second-largest city of Mosul, home to 1.5 million people, in June 2014.

This lesson of Samarra now looms over the West. Islamic State is using the same playbook in its attacks on Western targets this year — be it the ones directly organized by the group, such as the Nov. 13 massacre in Paris, or ones apparently only inspired, such as the shooting in San Bernardino.

The group’s objective is clear: to try to bait Western societies into an indiscriminate backlash against millions of Muslims living in Europe and the U.S. It is a backlash that, if successfully provoked, would disrupt these Muslims’ bonds with their countries of citizenship and residence and — as is it happened with Iraq’s Sunnis — validate Islamic State’s claim to be their only protector.

“ISIS thrives on polarization,” said Hassan Hassan, an expert on the group at the Royal Institute of International Affairs in London. “They want people to say — they hate us, and so we hate them. This is the foundation of their success.” [Continue reading…]