Don’t Rely on U.S. Law to Prevent Escalation in the Middle East


Following the Palestinian militant organization Hamas’ attack on Oct. 7, the U.S. government acted swiftly to dissuade other regional actors such as Hizballah or Iran from intervening in the latest round of Israeli-Hamas hostilities. The attack killed over 1,400 Israelis, mostly civilians, and resulted in another 3,500 wounded, 102 of them seriously. Hamas also took over 200 hostages, which included a number of foreigners, including 26 children. In response, Israel initiated Operation Iron Swords, and as of Oct. 19 the military campaign, according to the Palestinian Health Authority (independent figures are unavailable), has killed approximately 4,317 Palestinians and wounded over 13,000, most of whom are civilians. The scale and brutality of Hamas’ attack and the intensity of Israel’s response, which far exceeds previous rounds of fighting in Gaza, have set the region on edge and raised fears about a multi-front conflict and regional war, an outcome the United States is actively seeking to deter. 

In his remarks on the attacks, President Joseph Biden was blunt: “Let me say again — to any country, any organization, anyone thinking of taking advantage of this situation, I have one word: Don’t. Don’t.” Backing up the president’s words, the Pentagon approved a deployment extension for the USS Gerald Ford carrier strike group in the eastern Mediterranean and redirected a second, the USS Dwight D. Eisenhower carrier strike group, which is on a regularly scheduled deployment and is now headed to the Middle East. Additionally, reports suggest that the United States is preparing further naval reinforcements, including ships carrying upward of 2,400 Marines, as a potential rapid reaction force. National Security Adviser Jake Sullivan has indicated that the United States has conveyed its position to the government in Iran through diplomatic channels, and Western allies have also urged restraint in their own conversations with Iranian officials. Biden’s visit to Israel, an active war zone not controlled by the U.S. military, is somewhat unusual for an American president and represents a further effort at signaling to all the regional parties.

Although the administration acknowledges the potential dangers of escalation, it is far from clear what might constitute potential triggers, much less U.S. responses or eventual endgames should deterrence fail. The potential for direct U.S. military involvement in a wider regional conflict is all too real, and an examination of the various vectors for potential escalation demonstrates how precarious the current moment is. Although Biden denied a report that the United States told Israel it would intervene in the event of a more serious conflict between Israel and Hizballah, other officials have carefully maintained ambiguity, whether as a further means of signaling deterrence or to keep open the underlying military option. 



The Biden administration should prepare for the possibility that deterrence alone may not prevent a wider conflict potentially involving the United States. As U.S. domestic law is unlikely to prevent America sliding into war, potentially without congressional authorization, action needs to be taken now to forestall U.S. entry into yet another Middle East war and a wider, destabilizing conflict. The U.S. government should urge Israel to pause its air attacks, continue to work on facilitating the movement of humanitarian aid in Gaza, and delay a ground offensive that appears imminent. This should lead to negotiations on further hostage releases and a full ceasefire.

A Regional Tinderbox

Should Israel pursue its stated objective of “toppling Hamas and destroying its military capabilities” through a potentially protracted ground invasion of Gaza, with all the civilian death and destruction that would inevitably entail, Hizballah may well step up attacks against Israel in the north, potentially initiating a cycle of escalation that could lead to full-scale war. Alongside the fighting, the dire situation of civilians in Gaza is further compounded by the unfolding humanitarian crisis following Israel’s near-total blockade of Gaza, which has meant that no food, fuel, or electricity is currently flowing to the besieged enclave. While the Israeli government announced the resumption of water supplies through one pipe reaching south Gaza, humanitarian organizations operating in the area have emphasized that this supply was temporary and wholly inadequate when compared to the needs of the entirety of Gaza. Egypt has been keen to resume normal operations at the Rafah border crossing, fearful of the potential spillover into North Sinai. Border operations were hampered by Israeli military actions and declarations that made clear that humanitarian convoys would not be allowed into Gaza. Following his meetings in Israel, President Biden indicated that he had reached an agreement to allow for humanitarian supplies to reach Gaza through Rafah. Operations were delayed because of an impasse over inspection modalities and the scope of humanitarian operations, but began fitfully over the weekend, although no fuel was allowed in. But the flow of aid is far below pre-war levels and incommensurate with the massive and growing needs of Gaza’s populace.

The images of human suffering produced by this conflict have already captivated the Arab world’s attention and generated outrage at the plight of the Palestinians. That crisis is set to deepen and will exert its own pressure on Hizballah, potentially compelling it to go beyond the limited action it has undertaken so far. There is also the looming danger of mass displacement of Palestinians from Gaza into North Sinai. While Egypt and other regional parties have expressed their vehement opposition to such an outcome, seeing it as creating potentially irreversible new facts on the ground, the logic of the war may push events in that direction. 

Alongside the fighting in Gaza, the situation in the West Bank also represents an additional escalation point that could impact the perceptions and judgments of Hizballah and others. The West Bank has been the scene of increasing violence over the course of the past year, marked by escalating attacks by Israeli settlers, often backed by the state. That period represents the deadliest year in decades for West Bank Palestinians, and in the days following the Hamas attack, there has been yet another spike in such violence, with Israeli forces and settlers killing more than 90 Palestinians in the last two weeks. 

But of course Hizballah and Israel are also locked in their own military conflict that has been contained by a fragile set of unwritten understandings that have come to define the rules of engagement between them. This modus vivendi has emerged through the periodic skirmishing that has defined this uneasy equilibrium since the ruinous 2006 war between the sides. So far these understandings about redlines that could trigger further escalation have held, but they are increasingly under pressure. Observers have largely assumed that mutual deterrence holds and that both Israel and Hizballah (and its external ally, Iran) seek to avoid a catastrophic repeat of the 2006 war, particularly in light of the current regional context and the possibilities for much wider and more protracted fighting this go-around. But these assumptions may be misplaced, and regardless of the intentions of the parties, misjudgments and mistakes may inadvertently draw them into conflict.

Regional Escalation Dynamics 

Escalation in one locale may also trigger actions farther afield, such as in Iraq and Syria, where U.S. interests and personnel may come up against militia actors linked with Iran. Indeed, on Oct. 17 and 18, U.S. forces in Iraq and Syria were targeted with drones, piercing the relative lull of recent months. On Oct. 19, a U.S. Navy destroyer in the Red Sea intercepted several cruise missiles and drones launched by Houthi rebels in Yemen, another armed group allied with Iran, which the U.S. military believes may have been aimed at Israel. 

Secretary of Defense Lloyd Austin recently acknowledged that deterrence would become more complicated as the fight in Gaza becomes more protracted and bloody. It would be a mistake to understand U.S. signaling through rhetoric and deeds as a symbolic gesture. For the Biden administration, whose senior national security officials are all veterans of the Barack Obama administration and participants in the redline incident in Syria, perceptions of U.S. credibility would likely be a major consideration shaping crisis response. It is not particularly difficult to imagine escalatory dynamics that could push the United States to actually use the warplanes aboard its aircraft carriers to strike at Hizballah. 

Setting aside the reputational costs of engaging in such a military endeavor, U.S. military action would likely pose a practical dilemma for U.S. policymakers, similar to what Israel is running up with against Hamas in Gaza: While much stronger than the Palestinian group, Hizballah is still operating as a militia, with no military infrastructure such as airfields and barracks or heavy equipment like tanks and battleships that airstrikes could target and destroy. Its strongest asset, up to 150,000 missiles and rockets — including an unknown number of precision-guided missiles that may be capable of wreaking massive damage on Israel’s infrastructure — are presumably embedded in residential areas. Taking out these weapons would require precise intelligence, but as is often the case, airstrikes in urban areas lead to widespread destruction and inevitable civilian casualties.

Notwithstanding the very real risks, U.S. domestic law is unlikely to serve as a significant hurdle preventing the Biden administration from taking the United States to armed conflict once again in the Middle East. Enabling legal doctrines and self-judging lawyering within the executive branch provide the president substantial latitude to use military force without congressional authorization. And with passions understandably inflamed by Hamas’ unspeakable crimes, what many have dubbed “Israel’s 9/11”, Congress may be all too ready to give the executive branch whatever authorization it seeks. 

Under the prevailing executive branch legal theories, the president has considerable discretion to use military force even without congressional authorization. According to the Department of Justice’s Office of Legal Counsel, whether the president may unilaterally use force depends on a two-part test — a test repeatedly invoked by administration witnesses during a recent congressional hearing on the use of force. The president must be able to establish, first, that the use of force serves a national interest, and second, that the nature, scope, and duration of the anticipated hostilities will not rise to the level of “war in the constitutional sense.”

The former prong, however, has been deemed to include everything from self-defense to regional stabilization, rendering it close to meaningless. Amongst the most obvious potential national interests the president might cite to justify the use of military force in the event of a large-scale Hizballah attack on Israel is the defense of U.S. nationals, given the presence of so many American citizens in Israel. Unsurprisingly, protection of U.S. nationals abroad has been the ostensible rationale for innumerable interventions over the last two centuries and indeed was part of the initial justification for the U.S. military campaign against the Islamic State of Iraq and the Levant.

The latter test prong, which is a safeguard against unilateral military action that by its “nature, scope, and duration” implicates, in the executive branch’s view, Congress’s Article I war powers, should in principle be more constraining. The Office of Legal Counsel has identified one particularly salient factor in reviewing whether an anticipated military operation amounts to this level of “war in the constitutional sense:” the risk of escalation. In assessing the risk of escalation, the Office of Legal Counsel has considered whether U.S. forces would suffer or inflict substantial casualties and thus has looked closely at the presence of ground troops given “the difficulties of disengaging ground forces from situations of conflict, and the attendant risk that hostilities will escalate.”

Although the Biden administration has been clear that it has no plans to put “boots on the ground” in Israel, there are thousands of U.S. troops deployed elsewhere in the region — including Iraq and Syria — subject to potential retaliation, if not directly from Hizballah or Iran themselves, then by other Iran-backed groups belonging to the so-called Axis of Resistance. The presence of such U.S. ground troops and the attendant risk of escalation against the United States should therefore weigh heavily in assessing whether U.S. intervention would constitute “war.”

In practice, however, this test has been applied unevenly by executive branch lawyers. Despite the risk to U.S. ground forces and likelihood of escalation, the Office of Legal Counsel blessed President Donald Trump’s killing of Iranian general Qassem Soleimani, which predictably led to Iranian retaliation against U.S. troops through ballistic missile strikes on Al Asad airbase in Iraq.

Further, the statutory guardrail designed to prevent the president from taking the country to war unilaterally, the 1973 War Powers Resolution, has been largely gutted by aggressive executive branch interpretation, adverse court decisions, and congressional acquiescence. To be sure, the law still notionally requires the president to withdraw U.S. forces introduced into hostilities within 60 days, absent congressional authorization to continue fighting. But executive branch lawyers have read “hostilities” very narrowly — for example, not to include waves of combat sorties flown against targets in Libya in 2011 — and also showed a creative capacity to delay counting to 60, as they did during the Tanker Wars of the 1980s.

Moreover, even if the White House conceded that congressional authorization to fight Hizballah was necessary or at least politically prudent, it is entirely possible that Congress would vote for such a war. Hawkish members of Congress were already discussing potential use of force authorizations against Iranian-backed groups even prior to Hamas’ massacre and kidnapping of civilians. Following the attack, the Chairman of the House Foreign Affairs Committee, Michael McCaul (R-TX), announced that he has been drafting an authorization possible targeting groups such as “Hamas, Hezbollah, and Iran-backed Shi’ia militias.” The overwhelming majority of U.S. legislators have rallied around Israel following the attack, and further escalation between Hizballah and Israel would likely further reinforce support on Capitol Hill. Considering the emotions of this current post-9/11 moment, it is entirely conceivable that a majority in Congress would vote for such a measure. 


The United States risks being drawn into an escalatory spiral in the Middle East. Domestic law will not prevent this. The best hope is diplomacy. The Biden administration should take further steps now to prevent the conflict in Gaza from widening. Recognizing that counsel of restraint will be unwelcome, the United States should nonetheless urge Israel to pause its air attacks, continue to work on facilitating the movement of humanitarian aid in Gaza, and delay a ground offensive that already appears to be in advanced stages of planning. At that point, talks on the release of all hostages could be given more time to succeed while also providing the parties an opportunity to begin framing the contours of a full ceasefire. This cannot be done without outside mediation, given the absence of direct contacts between Israel and Hamas. Qatar (which reportedly played a role in the release of two U.S. hostages) and Turkey, along with Egypt (which also has extensive experience in this regard), are obvious candidates to play this role.

The obvious counter to our argument is that the United States should not restrain Israel and that its own self-restraint when attacked by Iranian-backed groups invites more attack. However, dramatic actions to “restore deterrence,” such as the Trump administration’s strike on Islamic Revolutionary Guard Corps leader Qasem Soleimani, led not to deterrence but to immediate escalation with Iran, through retaliation against U.S. personnel. We believe that while military force is a useful tool for diplomacy, it is not the only one. The costs of either Israel or the United States embarking on an expanded or new conflict with no clear or readily obtainable objective outweigh the likely security benefits. The collateral effects of such an endeavor would likely be severe in terms of civilian casualties, regional stability, and U.S. interests. 

The failure to pause and instead proceed with a purely military solution could lead not only to a humanitarian catastrophe in Gaza and a dangerous, destabilizing escalation throughout the Middle East, but also to the United States once again going to war with no endgame. Secretary Austin recently invoked the post-9/11 lesson that “you have to really think through next steps. … Don’t operate on reflex activity. Think through what you’re going to do, what implications it’s going to have for the country, for the region and beyond.” This is sound advice, and the Biden administration should follow its own admonitions. The White House needs to think now about how to prevent a worsening war in Gaza that draws Hizballah and even the United States into armed conflict. Military deterrence alone may prove insufficient.



Brian Finucane (@BCFinucane) is senior adviser with the U.S. Program at the International Crisis Group. Prior to joining Crisis Group in 2021, he served for over a decade as an attorney-adviser in the Office of the Legal Adviser at the U.S. Department of State. He is a Non-Resident Senior Fellow at the Reiss Center on Law and Security at NYU School of Law.

Michael Wahid Hanna (@mwhanna1) is U.S. Program Director at the International Crisis Group and a Non-Resident Senior Fellow at the Reiss Center on Law and Security at NYU School of Law.

Image: U.S. Navy photo by Mass Communication Specialist 1st Class Gary A. Prill