Possible Military Implications of a US Military Withdrawal from Syria

On 19 December 2018, President Trump announced that the Islamic State of Iraq and Syria (ISIS) had been defeated in Syria and that US forces would be withdrawn. While not wishing to comment on the politics of this decision and how it was made, this short initial article addresses some of the military implications of a US withdrawal.

The military situation in Syria involves many actors: President Assad’s Government forces, Syrian anti-Assad forces, ISIS, Al Qaida (AQ), Hizballah, Iran (Islamic Revolutionary Guard Corps (IRGC)), Russia, Turkey, Kurdish forces, and Allied forces (UK, France etc). It also affects others such as Israel and Iraq. Each of these forces has its own interests for being involved (for example: defeat of ISIS, support of Assad, overthrow of Assad, containment of Iran, protection of Israel, etc). Indeed, many have multiple interests that could create different problems as the situation changes. Such a complex situation requires careful actions to influence each actor towards one’s desired outcome.

Writing within hours after the ambiguous announcement, it is still unclear as to what the extent of the US withdrawal will be (nothing has been posted to the White House or DoD websites). The presence within Syria is small, but supported by regionally-based assets. While the physical presence creates influence effects of itself, the military capabilities generated require the regionally-based force elements (for example: deterrence, small-scale conventional combat, unconventional warfare, intelligence, combat search and rescue (CSAR), close air support (CAS), counter-terrorism direct action, and training of partner forces).

President Trump’s announcement only mentioned the defeat of ISIS, and while they have lost considerable territory and personnel, for many reasons it can be argued that they not defeated, and not other US interests in Syria. He also stated that it is time for other countries to take the burden in Syria. Unfortunately, it cannot be assumed that any other actors that involve themselves in Syria would share all, or even some, of the US national interests, for example the safety of Israel’s border. Indeed, even if a country did share common interests with the US in Syria, their involvement may be dependent on capabilities that the US withdraws, for example: intelligence, CAS and CSAR.

Until clarification of the withdrawal is provided it is unclear as to how it will affect the current or prospective actors in the region militarily, although some are already exploiting the announcement through international media.