The volley of attacks and counterattacks between Iran and Israel in the first two weeks of April drastically changed the strategic landscape in the Middle East. On April 1, an Israeli airstrike on the Iranian consulate in Damascus killed seven Islamic Revolutionary Guard Corps commanders, including two generals. Two weeks later, Iran retaliated with a barrage of drones and missiles, almost all of which were intercepted. Israel swiftly responded with its own drone and missile attack on an airbase in Iran. The exchange brought the shadow war the two countries have been fighting for more than a decade into the open.

It is now clear that the spiraling rivalry between Iran and Israel will shape regional security and drive Middle East politics for the foreseeable future. Each views the other as an arch enemy that it must defeat by military means. Left unchecked, their dangerous competition will destabilize the region, and it could ultimately trigger a conflict that drags the United States into a costly war. It now falls on Washington to craft a diplomatic strategy to calm the escalatory forces that precipitated a direct confrontation between Iran and Israel in April—and could do so again.

THE SPECTER OF A LARGER WAR

Hamas’s October 7 attack dented Israel’s aura of invincibility and diminished its sense of security. Israel has launched a ferocious response, seeking to destroy Hamas, free the Israeli hostages that remain in Gaza, and restore confidence in its ability to deter outside attacks and protect its population. All three goals have thus far eluded Israel.

Israel’s strike on the Iranian consulate, like its campaign in Gaza, was in part motivated by the desire to ensure an attack on the scale of October 7 can never be repeated. The strike killed Mohammad Reza Zahedi, the Revolutionary Guard commander who coordinated the military operations of Hezbollah in Lebanon, the Houthis in Yemen, and other armed groups in the region that Tehran has mobilized in support of Hamas in the past six months. By targeting Zahedi, Israel made clear that it considers Iran to be ultimately responsible for the current crisis. And by killing him in a diplomatic compound, it demonstrated its willingness and ability to assassinate senior Iranian officials anywhere and at any time.

This was not the first time Israel had struck Iranian bases in Syria or killed senior Revolutionary Guard officers and commanders there. Even before October 7, Israel had attacked Iranian industrial infrastructure and military installations, killed nuclear scientists inside Iran, struck bases used by Iraqi Shiite militias close to the Iraqi-Syrian border, and routinely targeted convoys of trucks traveling from Iran to Syria through Iraq. Israeli attacks in Syria became more brazen beginning in early 2022, when Russia, having reduced its footprint there to focus on Ukraine, no longer served as a check on where and when Israeli jets and drones could strike.

Iran generally refrained from responding directly. The last time Iran engaged in a tit for tat with Israel was in February 2018, when Israel replied to an Iranian-operated drone entering its airspace (an accusation Tehran denied) with a strike on Iranian positions in Syria. A skirmish followed in which Syrian forces shot down an Israeli F-16 fighter jet. Iran had since avoided direct confrontation in favor of what it calls “strategic patience,” focusing on building its military capabilities in Syria and abstaining from measures that could result in escalation with Israel.

But when Israel attacked its consulate, Iran changed its strategy. It interpreted the move as a significant provocation that called for a direct response. Iran’s leaders saw little reason to assume that Israel would not escalate further—not just in Syria, but in Lebanon and even in Iran—if they failed to restore deterrence.

The scale of Iran’s reaction, however, was both surprising and worrisome. Tehran did give notice of its intentions, communicating its planned response to the United States through European and Arab intermediaries. Then, by launching hundreds of drones and missiles at Israel, Iran made clear that it would no longer practice strategic patience and henceforth would respond when attacked.

Israel repelled most of Iran’s drones and missiles with help from Jordan, the United Kingdom, and the United States. Tehran likely expected such an outcome. Iran’s intent was not to provoke a war but only to demonstrate its willingness to attack Israel. Still, Israel retaliated, launching a missile strike on a major military airbase in central Iran. That strike seems to have ended this round of reciprocal attacks, but it also confirmed that the rules that guided Iran and Israel’s shadow war for years no longer apply. Now, an attack by either side will invite a direct response by the other, raising the specter of a larger war.

LOWER THE TEMPERATURE

Washington and its allies want to avoid such escalation—and Tehran knows this. Immediately after the Damascus consulate attack, the United States and its partners across Europe and the Middle East acted quickly to prevent the crisis from spiraling into war. The United States assured Iran that it did not know of Israel’s plans for the strike in advance and then signaled its concerns about the dangers of a larger war both in public statements and via intermediaries. Arab and European diplomats, carrying messages from Washington, spoke to Iranian officials directly. They urged Tehran not to respond at all but also emphasized that if a response were to happen, it should be measured, with a limited scope and range of targets, so as not to provoke further escalation. After Iran retaliated, Washington and its allies redirected their efforts, this time leaning on Israel to temper its response.

The diplomatic surge succeeded in keeping the crisis contained. It also made clear that the United States’ highest priority is to prevent the war in Gaza from igniting a regional conflagration and dragging the United States into another costly war in the Middle East. A fact working in Washington’s favor is that neither Iran nor Israel is keen on direct conflict, their recent show of force notwithstanding. Iran understands that Israel is a nuclear state with superior conventional capabilities and that war with Israel would ultimately mean war with the United States. Israel, for its part, knows that a larger conflict with Iran would compel Hezbollah to fire many more missiles at Israeli cities and military facilities. Still, if the tenuous truce between Iran and Israel is to hold, Washington must remain deeply engaged. It must work closely with Israel to address the country’s security concerns, and it should build on the diplomatic progress it has made with Iran in recent weeks.

Meanwhile, the prospect of another dangerous escalation looms over the region. An Israeli incursion into Rafah could precipitate another confrontation if Iran and its allies feel compelled to take action as the humanitarian crisis there worsens or to prevent the annihilation of Hamas. A long-term cease-fire between Israel and Hamas, too, could set the stage for further conflict, because it would free Israel to focus on Hezbollah—as it has hinted it intends to do—or once again target Iran in Syria. Iran and Israel are not ready to fight now, but if they continue to see each other as a mortal threat that can only be confronted militarily, then a future conflict is all but certain.

MOUNTING RISKS

Both countries’ preparations for that conflict will alter the region’s security balance in several ways. The first is through an arms race—after their recent military exchange, Iran and Israel will accelerate their pursuits of more advanced offensive and defensive capabilities. Because Iran and Israel do not share a common border, a war between them is less likely to require tanks, artillery, and soldiers than it is to be fought with missiles and drones—and, on the Israeli side, fighter jets. Amassing these weapons will not only make a war between the two enemies more likely and more devastating; it will also spur a destabilizing military buildup across the region. And Tehran, knowing that it will not likely be able to keep up with a conventional arms race, may redouble its efforts to secure nuclear weapons.

Both countries will also be looking to gain a geographical advantage. In the recent round of attacks, the relative effectiveness of Iranian and Israeli strikes depended not only on technological capabilities but also on their launch positions. Iran’s drones and missiles had to traverse Iraq and Jordan to reach Israel, reducing the element of surprise and providing Jordan, the United Kingdom, and the United States the opportunity to intercept a significant number before they reached their targets. Israel, by contrast, likely launched its attack from Iraqi airspace right across the Iranian border.

Iran has long pursued a strategy of arming Hezbollah with missiles on Israel’s borders while trying to deny Israel a similar perch in countries surrounding Iran. Tehran did not call on Hezbollah in the latest back and forth, but it could next time. Iran may also seek to augment its missile and drone capabilities in Syria, which shares a border with Israel. This would present a significant threat to Israel, which would likely respond by stepping up attacks on Iran’s and Hezbollah’s positions in Lebanon and Syria. U.S. troops that remain in Syria to fight the Islamic State (also known as ISIS) could thus be drawn into another mission: preventing an Iranian military buildup that could trigger an Iranian-Israeli war.

As Iran strengthens its military capacity on Israel’s borders, Israel may reciprocate by entrenching its intelligence and military presence on Iran’s borders. Azerbaijan and the Kurdish region of northern Iraq are already staging grounds for Israeli operations. Israel will likely expand that footprint, which will invite Iranian diplomatic and military pressure on both Azerbaijan and Iraqi Kurdistan. Iran recently conducted large-scale military maneuvers on its border with Azerbaijan and has launched missiles at alleged Israeli intelligence bases in the Kurdish region of northern Iraq. Such pressures could grow more intense. Azerbaijan and the Kurdistan Regional Government may then look to Turkey and the United States for diplomatic support and air defense. Turkey might be able to mediate between Iran and Azerbaijan, but only the United States can provide protection to the KRG—and such protection would likely require a strengthened U.S. military presence.

The potential expansion of Israel’s partnerships in the Persian Gulf could be even more consequential. Israel has close formal ties with Bahrain and the United Arab Emirates, and those countries, along with Saudi Arabia, collaborate with Israel on intelligence and security issues. But Israel does not yet have a base of operations in this region from which it could target Iran directly. Even before October 7, Iran feared a U.S.-brokered deal in which Israel would attain a base in Saudi Arabia that would be protected by an American defense pact with Riyadh. As Saudi public opinion has turned sharply against Israel since the onset of the war in Gaza, that prospect is not imminent. But stalled Israeli-Saudi normalization talks will not stop the United States and Saudi Arabia from deepening their strategic partnership. That partnership would inevitably become entangled in the Iranian-Israeli conflict, jeopardizing the Gulf states’ security and undermining their economic ambitions.

For these countries, the possibility of a defense pact with Washington presents a conundrum. They crave such an assurance, but it would also make them targets in any conflict involving Iran. Iranian missiles can reach their shores in seconds; a diplomatic agreement does not change that fact. Ironically, a defense pact is more attractive in a scenario in which the United States and Iran have lowered the tensions among them.

The Gulf states are therefore likely to try to stay in the gray zone between Iran and Israel, at least for now. But maintaining a balance will become more difficult as they face pressure from each side to deny the other access to their territory and airspace. Israel will press Washington to use its influence in Gulf capitals to secure cooperation, whereas Iran will threaten consequences for those who cooperate. Arab populations incensed by the war in Gaza will also pressure their governments not to help Israel. Jordan, for one, has discovered the difficulty of navigating these hardening battle lines. It followed the United States’ lead to shoot down Iranian drones heading for Israel, but popular criticism for that decision has pushed the government to step up its criticism of Israel’s conduct in Gaza.

Iraq will suffer more than any other country in the tug of war between Iran and Israel. Already, Iran has used Iraqi territory and militias to support its own operations in Syria and to attack U.S. bases in Iraq and Syria, and Israeli intelligence has carried out operations inside Iran from the Kurdish region of northern Iraq. During the recent confrontation, Iranian drones and missiles flew over Iraq to reach Israel, and Israel likely launched its attack on Iran from Iraqi skies. Iraq will only become more important as a first line of defense against Iranian missile attacks, which could encourage the United States to retain and even expand its military footprint in the country. For its part, Iran will intensify pressure on the Iraqi government to push the United States out. Shiite militias, for example, may increase their attacks on U.S. military installations and personnel in Iraq. Tehran will also want the KRG to cease cooperation with Israel and the United States. Iran has already carried out missile attacks on targets in northern Iraq it claims are linked to the Mossad, Israel’s intelligence agency, and the KRG has asked for U.S. air-defense protection against Iran. All these proxy battles will put Iraq’s tenuous stability at risk.

A RETURN TO STATECRAFT

Escalation between Iran and Israel could compel the United States to abandon its plans to reduce its military footprint in the Middle East. If Washington’s goal is to avoid entanglement in a regional war, then it must ensure regional stability. Washington’s instinct may be to rely on its military muscle to deter Iran, but in truth it needs a primarily nonmilitary strategy to contain and manage the conflict. To start, it should deploy the full force of its diplomatic power to work toward an end to the war in Gaza, followed by a serious and sustained pursuit of a viable Palestinian state. This outcome is necessary to build a broader regional order that constrains the escalatory impulses that now drive both Iranian and Israeli decision-making. The war in Gaza has intensified those impulses, and only by ending it can the tensions simmer down.

The end of one war must not be the beginning of another in Lebanon. Israel and Hezbollah will need to restore the cold peace they had maintained between their war in 2006 and October 7 last year. Success on this front, combined with steps toward a political resolution of the Palestinian issue, is critical to meaningful normalization of relations between Israel and Saudi Arabia, as well as between Israel and the rest of the Arab world.

The final piece of the puzzle is Iran itself. Managing the threat Iran now poses to Israel must go beyond arming Israel and instilling fear of U.S. retaliation in Tehran. The United States must also consider a diplomatic push, similar to its efforts to mediate between Israel and Hezbollah over the past six months, to establish redlines between Israel and Iran. Each side would clarify the kinds of provocations they would view as cause for escalation and make a tacit agreement to avoid crossing those thresholds. For such a process to begin, though, the United States and Iran must reduce their own tensions by renewing the discussions about Iran’s nuclear program and regional issues that they started in Oman last year but abandoned after October 7. It is in the United States’ interest to resume these talks, which could lower the temperature between Iran and Israel. Such de-escalation is necessary before any diplomatic breakthrough regarding Iran’s nuclear program—an urgent issue made more so by the Iranian-Israeli rivalry—is possible.

The silver lining to the crisis in April was that Washington and Tehran talked behind the scenes throughout the two weeks. Their communication was key to averting catastrophe. As it charts its next diplomatic course, the United States should take advantage of that opening to lower the risk of a larger war. It should engage Iran on a host of regional issues, such as the Houthi threat to international shipping in the Red Sea, and build on its previous diplomatic efforts to bring calm to the Israeli-Lebanese border. This is not a time for the United States to fall back on military options as the solution of first resort. The region’s perilous security conditions instead demand that Washington realize the potential of American statecraft.