FALLUJAH, Iraq—For Islamic State, this city was unlike any other: the birthplace of its movement and the first urban center it seized in a blitz that began the occupation of a third of Iraq.

But it took Iraqi forces less than five weeks to defeat the extremist group here, much faster than Iraqi and American officials had expected. One reason, these officials and Iraqi commanders say, was how invested Islamic State was in Fallujah, which made them loath to blow it up.

“Fallujah was a command-and-control center,” said a senior Iraqi counterterrorism officer. “They were comfortable there. Their leadership lived there and so did their families. They could not destroy the city in the process of defending it.”

Commanders said the militants had bet on repelling Iraqi forces on the outskirts of Fallujah, but struggled to adapt to the overwhelming force. The center of the city was still inhabited—one reason it wasn’t booby-trapped, as Islamic State had done in other, largely deserted urban areas they lost.

As Iraqi forces took central Fallujah in a quick three-day push, they discovered just how entrenched Islamic State was. There were administrative offices and courts, jails concealed behind the facades of opulent homes, huge bomb-making factories and do ents detailing 266 suicide-bombing operations in Baghdad.

There were also functioning medical clinics, supermarkets and restaurants.

The difference was visible on recent visits. The southern outskirts bore the evidence of intense firefights, airstrikes and s ing with whole buildings reduced to rubble and others leaning precariously. Some roads were caved in, lined by deep trenches and littered with burned-out vehicles.

Deeper into the city, many buildings appeared untouched or with only a few bullet holes, indicating fighting had been light. Iraqi security forces gathered in well-appointed homes complete with flat-screen TVs as well as fundamentalist books on female chas y and other topics.

Lt. Gen. Raed Shakir Jawdat, the commander of the federal police force that sent 6,000 troops into Fallujah, said his officers recovered paperwork and ledgers that meticulously do ented the nationalities and living arrangements of Islamic State’s foreign recruits and their families.
http://www.wsj.com/articles/fallujah...-it-1467214377