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"In January 2014, ISIL took control of Fallujah and Ramadi, inciting conflict with the Iraqi army. On 4 June, the insurgents began their efforts to capture Mosul. The Iraqi army had 30,000 soldiers stationed in the city, facing a 1,500-member attacking force."
This is the same Iraqi army that was trained and heavily armed with vastly superior weaponry of all forms by the US.
Were it not for NATO's aerial bombing the Shia and Kurds of Iraq could have gone the way of the Sunni Persians after the Safavid ascendency in Iran.
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"KUDILAH, Iraq — It is April, and fighting is stalled, with part of the Iraqi army forces camped at the village of Kudilah and unable to advance because of fierce resistance and counterattacks by the so-called Islamic State. The research team that first came here in February to talk to fighters on all sides about a ferocious battle that was supposed to be over, or at least ending, is continuing its interviews.
Our aim is to better understand the “will to fight.” President Barack Obama and his National Intelligence Director, James Clapper, have called this “the imponderable” that has led to an overestimation of the allied ability to degrade and destroy Islamic State forces and an underestimation of their ability to resist.
...
If you look back to August 2014—less than two years ago, it is worth noting—ISIS looked like it might just be unstoppable. It had taken Mosul in June, virtually without a fight, and now it was rolling across northern Iraq. To the south and east, its fighters crossed the Tigris River, reaching the town of Makhmour. Further north, they pushed across the Great Zab River, a Tigris tributary, at Gwer (also known as al Kuwayr).
ISIS was now within striking distance of Erbil, the capital of the Kurdish Regional Government of Iraq (KRG), a quasi-state wrenched from Saddam Hussein’s control and established in 1992 under America’s “No Fly Zone” following the first Gulf War.
...
At one point, KRG President Masoud Barzani, who also heads the Peshmerga forces, told U.S. Central Command that it was only a matter of hours before Iraqi Kurdistan fell, and with it perhaps all of Iraq.
President Obama, pulled from a D.C. restaurant where he was dining with his wife, was told that unless U.S. air power entered the fray immediately the whole region could be lost.
The only forces not in full retreat were Turkish Kurds of the PKK, a Marxist-Leninist group that’s on the U.S. list of terrorist organizations, which pushed to the front of the line near Makhmour, and the PKK’s Syrian affiliate, YPG, which was punching a narrow corridor through ISIS lines from the Syrian border to Mount Sinjar in the west in a heroic effort to save the besieged Yazidis there.
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ISIS sent four suicide car bombs to stall the advance: coalition planes knocked out two, a French-made Milan anti-tank missile hit another, and the fourth blew up before engaging. Peshmerga cleared the village by noon, then withdrew to the rear after deploying Sunni Arabs throughout the town. Major Amin’s forces stayed through the night, clearing some 80 IEDS to secure the approach between Kudilah and the Burj forward outpost.
Between 9 and 10 p.m. the next evening, ISIS launched a counterattack spearheaded by up to 17 inghamasi, (“those who dive in deep,” fighters wearing suicide vests who often lead the attack), killing five Arab tribesmen and wounding several other Arabs while taking one of Kudilah’s two positions on high ground.
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One wounded 15-year-old ISIS fighter was taken alive, but we couldn’t find out anything about him as KRG intelligence whisks away captured fighters who are not immediately executed into some dark hole. Gen. Ziryan, who had been fighting since the 1970s against Saddam Hussein and successive threats, told us that fending off the ISIS counterattack was the hardest battle he’d ever fought. “The Daesh emirs [leaders] fight until they die,” Ziryan said.
As Karzan put it: “They were coming at us full of heart, with full commitment to their beliefs. It was much more vicious than Fallujah or Ramadi. ‘Death or victory.’ They would not retreat until our reinforcements overwhelmed them.”
“And then,” said Shkak, “I heard the explosions of five or six or seven inghamasi who blew themselves up to cover the retreat. It’s hard to know anything for sure in the fighting all around you.”
The battle seemingly was won. But it wasn’t.
Coalition forces could hear Abu Ali, commander of the ISIS forces in the battle, exhorting his soldiers over the walkie-talkie to retake Kudilah from the Crusader Coalition at all costs on direct orders from Caliph Abu Bakr al-Baghdadi.
The fierce determination of ISIS soldiers to fight on against overwhelming force ultimately convinced the Sunni Arabs not to redeploy in Kudilah without the continued presence of the Iraqi Army, which was ordered to withdraw, or the Peshmerga, who didn’t want to occupy an isolated position surrounded on three sides by ISIS-held villages, however strategically important. And so the Arab tribesmen withdrew as well.
The Islamic State’s local news bulletin, Al-Naba Wiliyat Dijlah, announced: “After vicious fighting with Peshmerga apostates and the Rafidhi mobilization forces [a reference to mostly Shia militia that did not in fact participate in the fight but are seen as the tail wagging the Iraqi army]… and intense air cover from the coalition of crusaders, the soldiers of the Caliphate managed, praise unto God, to wage a counterattack that led to re-control [of Kudilah] at dawn of Saturday Rabia’ al Akher [Feb. 6] after two days of heavy fighting.”
Note well that the only group with zeal even coming close to the Islamic state was that of a Kurdish-Marxist terrorist group.
One of the most common themes of history is that of highly cohesive, organized and aggressive minorities willing to die for their cause ascending to power in much larger civilizations, and then remaking the conquered peoples in their own image, or, at least leaving, an ineluctable presence in those lands.
The Islamic State has the honour of belonging with the Mongols of Genghis Khan in their capacity for conquest - and it is only in virtue of human capital transforming foreign warfare that they are unable to replicate the success of their ancestors.
If the Islamic State comes to the US the fact is that - unless the US were to take off its gloves and unleash hell on its own soil - Americans would fare no better than the Shia and Kurds of Iraq in being trampled by and potentially conquered by the Caliphate.