As tensions with Iran remain high, the Pentagon and NATO have paused the training of Iraqi police and military units over concerns of insider attacks.

Military officials are concerned that fighters from the Popular Mobilization Units (PMUs), Shia militant groups and Iranian proxies, might have infiltrated the ranks of the Iraqi police and military. (Historically, green-on-blue attacks have been more common in Afghanistan.)

These concerns are fairly well-grounded. Shia Muslims are a majority in Iraq and they control much of the government, which, in turn, is under the influence of Tehran. Numerous American and NATO units in the country are housed or work on the same bases as the Iraqis.

Iraqis mourning the death of Major General Qassem Soleimani and paying respects to his coffin. Note the member of the Iraqi Special Operations Forces (ISOF) on the bottom left. Most of his equipment is American (he even sports the Punisher patch…). ISOF members have been operating alongside American Special Operations units in the fight against the Islamic State. The threat of an insider attack in one of the many American SOF elements in the country, which include Navy SEALs, Marine Raiders, and Green Berets, is high. 

“We continue to take all precautions necessary,” said NATO spokesman Dylan White in a statement. “NATO’s mission is continuing, but training activities are temporarily suspended.”

NATO’s presence in Iraq comes in the form of several hundreds of troops. Part of the NATO Mission Iraq (NMI), the troops are there to train, advise, and support the Iraqi military. Led by the Canadian Major General Jennie Carignan, NMI is comprised of troops from both NATO and non-NATO partner countries.

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Concerns over insider attacks notwithstanding, most of the Iraqi police and military have been staunch partners in the fight against the Islamic State.

As Iran prepares its response to the targeted killing of Soleimani, the Pentagon is prepared for everything. After a few days of radio silence, President Trump spoke about Iran’s threats: “Iran is talking very boldly about targeting certain U.S.A. assets as revenge for our ridding the world of their terrorist leader who had just killed an American, & badly wounded many others, not to mention all of the people he had killed over his lifetime, including recently hundreds of Iranian protesters.”

Anticipating a response from Tehran, Trump warned that the U.S. military is ready to respond to any Iranian retaliation.

“Let this serve as a WARNING,” he said in a Tweet, “that if Iran strikes any Americans, or American assets, we have targeted 52 Iranian sites (representing the 52 American hostages taken by Iran many years ago), some at a very high level & important to Iran & the Iranian culture, and those targets, and Iran itself, WILL BE HIT VERY FAST AND VERY HARD. The U.S.A. wants no more threats!”

Iran has signaled that any response to the killing of Soleimani will come after the ending of a three-day mourning period. Tehran has many arrows in its quiver, from cyberattacks to terrorist strikes on soft U.S. targets, to diplomatic maneuvers that could keep the U.S. from Iraq, thereby cementing Iran’s influence over its strategic neighbor. Whatever the response, Tehran has had a history of cautious and calculated moves, so don’t expect any rush ones.