During a visit to Baghdad, Secretary of Defense Ash Carter announced that the United States will deploy an additional 560 troops to Iraq to assist in the fight against the self-declared Islamic State in Iraq and Syria (ISIS).
That will bring the number of American forces in Iraq to almost 6000, far higher than the Pentagon-cited figure of 4,647 - the Defense Department does not include personnel on temporary assignments in the official count.
The stated reason for the additional troops is to assist Iraqi forces as they prepare for the eventual campaign to retake the city of Mosul. Mosul is Iraq's second largest city - it has been under ISIS control since it fell to the group in June of 2014. One of the tasks assigned to the new troops will be the rehabilitation and reconstruction of facilities at the large al-Qayyarah air base - the base was recaptured from ISIS on July 9.
The base will be a key staging area for Iraqi forces as they mount the attack on Mosul. The base is about 40 miles south of Mosul and west of the Tigris River. This assault was successful in crossing the river and reclaiming territory from ISIS west of the Tigris Valley, further reducing the amount of Iraqi territory in the country under the group's control.
The air base, formerly known as al-Qayyarah West, is a large facility with long runways capable of handling heavy transport aircraft, as well as scores of helicopters. The base provides an excellent base from which to launch attack sorties against ISIS positions in Mosul. Additionally, Iraqi or American long-range artillery or rocket launchers will complement the existing American firebase located at Makhmur on the east bank of the Tigris.
The recapture of the air base is an important step, one of the many needed before the operation to liberate Mosul can start. The liberation of Mosul is necessary to defeat ISIS and eject them from Iraqi territory - it is the group's major holding in the country. Mosul and the Syrian city of al-Raqqah, which ISIS claims as its capital city, are major centers of gravity for the group.
The loss of Mosul will effectively end their claims on Iraq. Only then can the government in Baghdad begin the rebuilding of the country as a viable, united political entity.
Preparing for a campaign to retake Mosul has been a long and slow process. The Iraqis have thus far expelled ISIS from Tikrit and Bayji (and now al-Qayyarah) in the Tigris Valley, as well as ridding the entire al-Anbar province by successful - if not devastating - operations in al-Ramadi, al-Hit and recently al-Fallujah.
It was hoped that the removal of ISIS from al-Anbar would reduce the number of ISIS bombing attacks in and around Baghdad - July was a month of a series of high-profile bombings in the city. Unfortunately, ISIS used its lingering presence in Diyala province (east and southeast of Baghdad) to launch the most devastating truck bombing in the upscale Shi'a neighborhood of Karradah on July 4. That attack, in which almost 300 people died, was the worst single attack since the invasion of Iraq in 2003.
Although the recapture of Mosul is arguably the key to the eventual defeat of ISIS in Iraq, the Iraqi government of Prime Minister Haydar al-'Abadi has another concern - the security of Baghdad. As long as ISIS is able to mount devastating bombings in and around the capital, the residents will demand that he focus on their immediate security rather than the eventual recapture of Mosul. Should al-'Abadi decide to allocate security resources - army, militia or police - to Diyala to deal with the ISIS threat emanating from that province, it will delay the Mosul operation.
The Mosul operation will be a large-scale undertaking. Retaking cities like al-Ramadi and al-Fallujah were much smaller operations, and took much longer than expected. Mosul is going to require virtually all of the combat power Iraq has and then some.
The "then some" will be the assets committed by the U.S.-led coalition - airpower, artillery and rocket fire support, intelligence, logistics, communications, command and control, engineer support, as well the placement of U.S. military officers in Iraqi combat battalions.
It is those capabilities that Secretary Carter cited in his remarks: "These additional U.S. forces will bring unique capabilities to the campaign and provide critical enabler support to Iraqi forces at a key moment in the fight."
The increased American support will be necessary for the Iraqis to recapture Mosul. As we have seen in recent military operations, there is great reliance on American airpower, intelligence, fire support, etc. Since Mosul will be a much larger, more complex operation, there will likely be calls for an even higher level of support.
The Administration's decision to deploy additional troops to Iraq reflects the realization that Iraqi forces as they stand today are not capable of conducting that operation, and certainly not on the timetable promised by Prime Minister al-'Abadi - he has pledged to retake Mosul before the end of the year.
To those of us who served in Vietnam, the gradual escalation of American troop presence in Iraq over the last two years reminds us of how a small advisory mission grew into a large-scale military operation lasting over a decade and costing over 58,000 American troops.
The words "mission creep" come to mind. It is not only the troop presence in Iraq that concerns many observers - it is the continuing build up of forces in the region that directly conduct operations against ISIS in Iraq and Syria.
It is critical that ISIS be defeated - and key to that defeat is the retaking of Mosul. Should the Iraqis prove incapable of doing that with the current levels of American support, will we continue to escalate our troop presence? Are we in danger of sliding further down that slippery slope? Are we going to reach the point when we see the re-introduction of American combat formations into Iraq?
We haven't even started talking about ejecting ISIS from Syria yet.