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The 2019-2020 Iran Crisis And US Military Deployments – Analysis


By Kathleen J. McInnis*

The January 2, 2020, U.S. drone strike against Iranian Major General Qassem Soleimani, the subsequent Iranian counter-strike on bases hosting U.S. personnel in Iraq, and recent deployments of U.S. military forces to the Middle East have prompted widespread concerns about whether the United States is preparing to engage in another major military campaign in the region.

Yet at present, the flow of additional forces into the U.S. Central Command (CENTCOM) area of responsibility (AOR) suggests that the Department of Defense (DOD) is posturing itself in the region defensively, with the ability to respond to aggression, if necessary. The design of this posture may be altered should there be changes to security or political conditions on the ground, or political objectives for the region.

Force Employment Goals?

The Trump Administration has stated that its “core objective … is the systemic change in the Islamic Republic’s hostile and destabilizing actions, including blocking all paths to a nuclear weapon and exporting terrorism.” Most recently, U.S. officials have argued that additional forces flowing in the region, as well as the strike against Soleimani, are intended to “re-establish deterrence.”

The military is but one tool of national power that could be used in a variety of ways to achieve the above stated U.S. objectives. These range from increasing presence and posture in the region to seeking regime change. As with any use of the military instrument, any choice to employ U.S. forces—or not—is an inherently risky endeavor and could result in retaliatory Iranian action and/or the further escalation of a crisis in unpredictable ways. Iran’s actions may influence U.S. force levels as much as or more so than U.S. plans.

Recent Deployments

Precise figures of deployed U.S. personnel are difficult to determine due to unit rotations in and out of a given theater. According to DOD, as of June 19, 2019, “there are approximately 60-80,000 U.S. troops in the U.S. Central Command area of responsibility,” including approximately 13,000 troops in Afghanistan and 5,200 in Iraq.

In recent months, the Pentagon has announced several troop and capability movements to and from the CENTCOM theater; with rotations, these announced deployments total approximately 10,000 additional troops.

Key announcements, which should be treated as illustrative rather than definitive deployment figures, include the following:

  • On May 5, 2019, then-National Security Adviser John Bolton announced that the United States was accelerating the previously planned deployment of the USS Abraham Lincoln Carrier Strike Group in response to tensions to the region and sending a bomber task force to the Persian Gulf area. The Lincoln was relieved by the USS Harry S. Truman Carrier Strike Group in December 2019.
  • On May 24, 2019, DOD said that the President approved a plan to augment U.S. defense and deterrence against Iran by deploying to the Gulf region an additional 900 military personnel, extending the deployment of another 600 that were sent earlier to operate Patriot missile defense equipment, and sending additional combat and reconnaissance aircraft.
  • On June 17, 2019, then-Acting Defense Secretary Patrick Shanahan announced that the United States was sending an additional 1,000 military personnel to the Gulf “for defensive purposes.”
  • On July 18, 2019, U.S. defense officials said that an additional 500 U.S. troops would deploy to Saudi Arabia. The deployment, to Prince Sultan Air Base south of Riyadh, reportedly will include fighter aircraft and air defense equipment.
  • On September 20, 2019, U.S. officials announced a “moderate” (widely interpreted as 200 personnel) deployment of additional U.S. forces to Saudi Arabia and the UAE. The forces reportedly accompany additional missile defense systems and combat aircraft sent to facilities in those countries, and are “defensive in nature.”
  • On October 11, 2019, U.S. officials announced the deployment of additional forces and capabilities to Saudi Arabia, including approximately 1,800 air defense personnel, fighter squadrons, and an air expeditionary wing.
  • In response to attacks on the U.S. embassy in Baghdad, on December 31, 2019, DOD announced the deployment to Kuwait of an infantry battalion from the Immediate Response Force (IRF) of the 82nd Airborne Division, with 750 soldiers to deploy immediately and additional forces from the IRF (about 3,000 military personnel) deploying thereafter. A small (likely platoon-size) element of the 173rd Brigade is also reportedly deploying to the region, possibly to Lebanon.
  • On January 5, 2020, DOD officials announced that a task force of U.S. Special Operations Forces, including Rangers, was deployed to the Middle East.
  • On January 6, 2020, DOD announced that the 26th Marine Expeditionary Unit was being directed to the Mediterranean.
  • On January 6, 2020, it was reported that DOD would be sending six 5-52 Stratofortress bombers to Diego Garcia in the Indian Ocean, to be available for operations in Iran, if ordered.

In the fall of 2019, the Trump Administration also assembled what it calls the International Maritime Security Construct, a coalition that monitors Iranian threats and could use military assets to protect commercial shipping in the Gulf. As of November 2019, the IMSC’s contributors included the United States, United Kingdom, Australia, Kingdom of Saudi Arabia, Albania, United Arab Emirates, and Bahrain.

Questions for Congress

These deployments raise a number of potential issues for Congress in its oversight and authorization capacities. These include the following:

What Might Be the Impact on Readiness and Availability of U.S. Forces for Other Missions?

Ultimately, any troops that are deployed to the CENTCOM AOR, as well as those training to replace them, will be taken out of the “pool” of forces available and ready to respond to other possible contingencies. DOD forces are a finite resource; the deployment of assets to the CENTCOM AOR will necessarily affect the availability of forces for other theaters and contingencies.

While the additional commitment of U.S. troops since this June has thus far been relatively modest, ongoing operations in Afghanistan (Resolute Support), Central and Eastern Europe (Operation Atlantic Resolve), and the unpredictable threat from North Korea could create a demand for additional U.S. forces that is not currently forecasted. DOD officials generally contend that force planning concepts, like Dynamic Force Employment, enable DOD to shift key U.S. military assets rapidly from one theater to another and can mitigate some of the risk associated with diverting resources towards CENTCOM.

Others question the robustness of Dynamic Force Employment and whether it sufficiently mitigates readiness and availability risks.

What Might Be the Impact on Regional and Global Basing and Posture?

U.S. expeditionary operations are enabled by a network of American bases and facilities hosted in allied and partner countries. Basing U.S. troops on foreign soil is a sensitive matter for host countries because such U.S. force deployments—which are generally subject to U.S. rather than host nation legal jurisdiction—are inherently in tension with a host nation’s sovereignty. As a result, the political- military relationships with the countries that host U.S. troops require careful negotiation and management.

Recent events, to include the Soleimani strike and Iranian counter- strike, could complicate bilateral negotiations on U.S. forward bases, both in Iraq as well as in other parts of the world. This may be particularly the case with regard to East Asia, which DOD officials have identified as their “priority theater” because of a need to keep pace with China’s actions, and where discussions are already sensitive due to U.S. concerns about burden-sharing issues.

Is DOD Adequately Prepared for Hybrid and Irregular Warfare?

While the aftermath of the January 8, 2020, Iranian missile counterstrikes is still evolving, many practitioners and experts note that the United States has heretofore primarily been engaged in a hybrid, irregular conflict with Iran for decades, with the exception of U.S.-Iran naval clashes during the 1980-1988 Iran-Iraq War.

Hybrid and irregular warfare are commonly understood to be instances when belligerents, to varying extents, collaborate with proxies (including, but not limited to, militias, other countries, criminal networks, corporations and hackers) and deliberately sow confusion as to what constitutes “civilian” versus “military” activities in order to create plausible deniability for a given action.

Many observers expect that the U.S.-Iranian relationship will return to a state of mostly irregular/hybrid warfare. However, given the Trump Administration’s overall strategic guidance to prioritize great power competition and lethality, some are concerned that insufficient attention and resources are being dedicated toward preparing U.S. forces to wage irregular/hybrid warfare.

Do Recent Deployments Align with National Strategy?

According to its strategy documents, in the Trump Administration’s view, effectively competing— economically, diplomatically, and militarily—with China and Russia is the key national security challenge facing the United States today.

As Iran reportedly is a lesser priority relative to these other challenges, some observers contend that a shift in U.S. resources away from the CENTCOM AOR and toward Europe and Asia is therefore necessary. Viewed in this light, recent deployments of forces and resources to the Middle East may create tension with the overall strategic goals of this Administration. However other observers, including the National Defense Strategy Commission, questioned whether this redirection of assets away from the Middle East was ever feasible.

*About the author: Kathleen J. McInnis, Specialist in International Security

Source: This article was published by Congressional Research Service (PDF)

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One thought on “The 2019-2020 Iran Crisis And US Military Deployments – Analysis

  • January 9, 2020 at 2:26 pm

    Another endless war


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