Defeating ISIL 'hell on earth' tactics in the coming battle for Mosul

Washington Free Beacon:

It’s not quite D-Day, but an array of armies, militias, tribal fighters, and Western support troops are massing for their “longest day” in Mosul.

Islamic State terrorists have held the historic city of Mosul for nearly two and a half years, and they have dug networks of tunnels and filled moats with crude oil to lay waste to a city that has been called an open-air museum.

“Essentially, they’ve built a hell on Earth around themselves and they’re going to be in that whenever the Iraqi security forces come in there and push them out,” Col. John Dorrian, a spokesman for the allied coalition, said Friday via video link from Baghdad.

Terrorist troop strength has been worn down by relentless attacks from the Iraqi regular army and by coalition bombing in Mosul and surrounding Nineveh Province. The number of terrorists inside the city is somewhere between 3,000 and 5,000—half the estimated number from two months ago, according to military observers.

Nonetheless, ISIS-built defensive barriers are a force multiplier. The terrorist force has dug 18-foot-deep trenches around the city and filled these with oil and tar. Black smoke from burning moats has the potential to obscure targets pursued by fighter aircraft and drones. Tunnels have been dug connecting both banks of the Tigris River and also the northern end of the city to districts near the Qayara oil fields, allowing fighters, weapons, and supplies to be moved quickly. Some tunnels discovered after the fall of Fallujah were miles long.

“We expect them to use the same tactics they employed in Manbij (a border city in northern Syria) whereby they will use civilians as human shields. They will use many tunnels. Terrorists dressed as civilians will go into a house in one part of the city and appear in another part of the city with weapons,” said Wladimir van Wilgenburg, a security expert affiliated with the Jamestown Foundation.

Iraqi counter-terrorism assault forces can expect houses, buildings, and streets studded with thousands of mines and improvised explosive devices, as well as car bombs and suicide bombers.
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There is much more.

While ISIL has had tenacious battles at some of the areas it once controlled, it has also killed its own fighters who retreated.  However, recently it has begun allowing the fighters to mix in with refugees and attempt to escape to defend other areas within its control.  This may be as a result of the fact that they are running short of fighters and can't afford to keep killing their own people.