U.S. forces have been acting officially as advisers in the battle to oust Daesh from Mosul, which began in October, though they have come closer and closer to the front lines and some are now carrying out combat operations with Iraqi troops.
At the invitation of the Iraqi government, former President Barack Obama recommitted troops to Iraq in 2014.
The U.S. military has acknowledged that the U.S. -led coalition probably had a role in the March 17 explosion, but said ISIS also could be to blame.
In early April, the Afghan ambassador to the USA claimed that by the end of Trump's first term, Afghan security forces would be sufficiently prepared to deal with jihadi terror groups in their country without the help of United States troops and advisers. Iraqi forces backed by US artillery and air power have retaken the eastern half of the city, and are battling to reclaim the western half in brutal urban combat.
The Obama administration formally withdrew USA forces, which at their highpoint numbered 170,000, in 2011. According to them, ISIS has so far lost more than 60% of its territory in Iraq.
"ISIS knows they're going to lose Mosul". Iraqis were eager to end what some saw as an occupation, and many Americans wanted to see an end to the then-eight year war.
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This includes the electrical system and landing gear, which are produced in the United States by Honeywell International. It was built by state-owned Commercial Aircraft Corp. of China or Comac.
"They knocked on our door but we did not open it".
What the long-term deployment would look like is still in the early stages, but it is believed USA forces in Iraq would be stationed inside existing Iraqi bases in at least five locations in the Mosul area and along Iraq's border with Syria.
However, the western part of Mosul, with its narrow streets and heavily populated neighborhoods, appears to be a bigger challenge to the Iraqi forces.
However, as the Iraqi army proved to be riddled with corruption and inexperience - and fearing the influence of Iranian-backed militias - the U.S. has gradually increased its ground presence in the country. No air strike was called - and the propaganda coup Islamic State would have reaped from the deaths of innocent people was averted. Those forces are operating even now without a SOFA, as their return was both rushed and unexpected.
Iranian Foreign Ministry Spokesman Bahram Qassemi on Friday evening expressed condolences to the Iraqi government and nation over an airstrike that has killed dozens of civilians at a disused school in western Mosul, including women and children.
Iraqi forces are struggling to retake the last remaining Mosul neighborhoods that IS holds in the city's western half, but even after a territorial victory, Iraqi and USA -led coalition officials have warned of the potential for IS to carry out insurgent attacks in government held territory.