David Schenker on the risks of a wider war with Iran and its proxies

A KEY ELEMENT of the Biden administration’s response to the war in Gaza has been the deployment of significant forces to the Middle East. So far America has dispatched, among other assets, two aircraft-carrier groups, their associated guided-missile destroyers and a Marine Corps expeditionary unit capable of conducting amphibious operations. According to America’s defence department, this armada is intended as “a strong signal of deterrence to any actors who might be thinking of entering the conflict”, an oblique reference to Iran and its regional proxy forces.

America’s display of force in the Mediterranean is impressive, to be sure—and there is more to come: the Pentagon says it will send a THAAD air-defence missile system and Patriot missile battalions to the region. But it remains unclear whether this muscle-flexing is actually curbing the involvement of other actors, or will prevent the war from spreading. For America’s deterrent threat to be credible, it will have to act decisively against emerging provocations.

Since the war started, Iran’s Lebanese proxy militia, Hizbullah, has been engaged in a calculated campaign of escalation along Israel’s northern border. The group has targeted Israel Defence Forces (IDF) positions with anti-tank missiles, disabled observation posts, attempted border infiltrations, and allowed if not encouraged Hamas and other Iranian-backed groups to fire rockets across the frontier.

Israel has responded, at times lethally but with restraint, in an effort to slow escalation. For its part, Iran has seemingly been hesitant to order Hizbullah into a full-scale war, preferring instead to preserve its most effective deterrent against potential Israeli military action aimed at Iran’s nuclear programme. Nevertheless, fears are growing that the current skirmishes could lead to miscalculation and another costly Hizbullah-Israel conflagration like the one in 2006—a 34-day conflict in Lebanon, northern Israel and the Golan Heights.

Iran, which for years sponsored, trained and equipped Hamas for what culminated in the slaughter of some 1,400 people in southern Israel on October 7th, has positioned itself as the defender of the Palestinian people. Even before the tragic explosion at the Ahli Arab hospital in Gaza on October 17th, the so-called “Arab Street” was boiling. As Palestinian civilian casualties mount, Iran will come under increasing pressure to follow through on its threats.

In anticipation of an Israeli ground offensive in Gaza, Iranian proxies are becoming increasingly aggressive, and not only on the Lebanon-lsrael border. On October 19th an American destroyer in the Red Sea downed four cruise missiles and 15 drones launched by Iran’s Houthi proxy militia in Yemen, which were apparently headed towards Israel. The same day, Iranian-backed militias in Iraq fired a salvo of rockets and drones, hitting two American bases in the country. And in southern Syria, Iranian proxies attacked an American garrison—retained to help rebel militias in the area fight Islamic State—and an oil facility housing American soldiers with drones.

These Iranian-sponsored operations are an unmistakable warning to Israel and America. But is Iran really prepared to make maximum use of its proxies?

How far the Islamic Republic goes in mobilising its client militias will be dictated by the success or failure of the IDF ground operations in Gaza—though escalation could result either way. If the Israeli operations go well, Iran could seek to broaden the conflict. If they go badly, it may look to exploit perceived weakness. It is also possible that the leaders in Tehran choose instead to limit the conflict, preserving their proxies’ capabilities to deter Israel from attacking Iran itself.

Ultimately, though, the key to avoiding a more regional conflict lies in Washington. American naval assets are positioned in the Mediterranean to deter a broadening of the war, but is the superpower’s threat to intervene viewed as credible? Perhaps it is bluster, but some Hizbullah affiliates are openly mocking the bolstered American regional presence. Other Iranian proxies are ramping up operations targeting American forces in Syria and Iraq.

If the Biden administration hopes to prevent more fronts from opening, America’s threat to intervene has to be seen as credible. The Biden administration hasn’t said it yet, but Iran is responsible for the war in Gaza. And if the war spreads, it will only happen because Iran gives the order. To discourage that from happening, America will have to respond decisively to attacks against its forces across the region. More important, instead of just focusing on the proxies, it will have to hold Iran directly accountable for the actions of its clients.

One way to do this is by increasing economic pressure. Last week America’s treasury department imposed a series of financial sanctions on Iran’s ballistic-missile and drone programmes. Beyond that, the Biden administration should make clear that the $6bn released to Iran in September as part of a deal to release five American detainees will be frozen in Qatar indefinitely. It could also roll out sanctions against companies linked to Iran-backed Iraqi militias. This step, along with measures to further restrict Iraq’s access to dollars—expanding rationing announced by America last year to combat corruption and money-laundering—would help curtail Iran’s sanctions-evasion activities.

More effective than financial tools, however, is military might. American reluctance to employ force in the region has allowed, if not invited, Iranian adventurism. To be sure, establishing and maintaining deterrence could itself risk an escalation. Iran and its proxies are well aware that America wants to avoid another armed entanglement in the Middle East—another factor undermining the credibility of American threats. Unfortunately, to forestall a widening of the war in Gaza, Washington may have no choice but to engage militarily.■

David Schenker is a senior fellow at the Washington Institute for Near East Policy and a former United States assistant secretary of state for Near Eastern affairs.