The Wars After the War: Why Israel and Iran May Keep Fighting

Commentary by Daniel Byman

Published March 11, 2026

The end may be in sight for the current war in the Middle East, with its massive U.S. and Israeli air strikes on Iran and Iranian attacks on U.S. regional allies and Gulf shipping. Even then, however, hostilities may not stop. One plausible future scenario is that the Iranian regime and Israel remain in a state of low-level conflict that involves cyberattacks, sabotage, terrorism, and the occasional overt military strike, with the United States perhaps joining in from time to time. For Israel, this will be a way to keep Iran weak and off balance, while Tehran will be striking back out of vengeance, to legitimize its tottering regime, and to restore deterrence.

The future of the Iranian regime is unclear, but one plausible scenario-perhaps the most plausible-is that it will emerge from the war weak but unbowed, and perhaps even more radical. Regime change is possible but unlikely, and the decision to choose Mojtaba Khamenei, the son of assassinated Supreme Leader Ali Khamenei, as his successor signals defiance and a strong role for the hardline Islamic Revolutionary Guards Corps (IRGC).

This regime might retreat to a corner and lick its wounds, but it might also seek revenge. With U.S. intelligence assistance, Israel killed not only Ali Khamenei, but also Iran's defense minister, the IRGC chief, and other senior officials-and these deaths are on top of the large numbers of security officials that Israel killed during the Twelve-Day War in 2025. Israel also decimated the leadership of key proxies, such as the Lebanese Hezbollah. In 2012, Iran and Hezbollah retaliated for the assassination of Iranian scientists by bombing a busload of Israeli tourists in Bulgaria. More recently, Iran has sought to assassinate senior U.S. officials involved in the 2020 killing of IRGC paramilitary leader Qassem Soleimani, among other retaliatory plots. Given the far greater scale of the 2025 and 2026 assassinations and the higher profile of those killed, Iran's incentives for striking back are high.

If revenge is not enough of a motive, a desire to restore deterrence may be. In general, Iranian officials are likely to believe that there is nothing they can do to alleviate U.S. and Israeli hostility, so they must instead deter or degrade their enemies before receiving a fatal blow. Before the series of conflicts triggered by the Hamas terrorist attack on Israel on October 7, 2023, Iran relied on its vast missile and rocket arsenal and strong proxy groups to deter U.S. and Israeli attacks. Since then, Israel has decimated Hezbollah and Hamas, two of Iran's most important proxies, and the 2025 and 2026 wars have destroyed or degraded much of Iran's missile and rocket forces. Militarily, Iran is weak and seemingly at the mercy of its foes. Iran may continue to back proxies and use what limited stockpiles it has to ensure that Israel, the United States, and other perceived aggressors know that they will pay a price if they strike Iran. This may also include continued strikes on, or at least threats against, the Gulf states, so they lobby the United States to be more accommodating.

The biggest question mark is whether Iran will seek a nuclear weapon. On the one hand, much of Iran's program is buried in the rubble of the 2025 U.S. and Israeli strikes, but U.S. and Israeli officials remain concerned that Iran could restart the program. Pursuing nuclear weapons would be a provocative step for Iran-Iran's nuclear program helped spark two wars, after all. In the regime's eyes, however, the U.S. abrogation of the Iran nuclear deal and subsequent attacks on Iran, even when Iran was not believed to be weaponizing its nuclear program, are proof that the United States and Israel are hostile. The regime might feel that it will be attacked regardless of whether it does or does not pursue nuclear weapons.

Finally, the postwar regime leaders may think that continued conflict is in their political interest. Even before the latest war, Iran faced rampant inflation, rising poverty, and other economic problems. These problems helped spark the massive protests throughout Iran that the regime suppressed brutally in January 2026. The destruction of the latest war will worsen this already disastrous situation. Having an external enemy, especially Israel and the United States, would be a way for the regime to justify repression at home and deflect blame for ongoing economic problems.

Just as Iran has reasons to keep the war going, so too does Israel. Israeli leaders seek to keep Iran and its proxies weak as long as the regime remains hostile. Well before October 7, Israeli leaders talked of the "campaign between the wars." The idea is to disrupt enemy forces to prevent buildup, bolster deterrence to reduce the likelihood of attack, and develop operational and intelligence access should more force be needed. In practice, this has meant limited, and at times covert, attacks, including airstrikes, cyber operations, and other measures that make any future war more likely to go in Israel's favor. For example, Israel targeted antiaircraft missiles going from Iran to the Lebanese Hezbollah via Syria in 2013 and conducted cyberattacks on Iranian nuclear facilities in 2021.

If Israel judges that Iran remains hostile, it is likely to conclude that a future war is probable and that more limited operations are necessary to ensure that Iran is weak and deterred and, should deterrence fail, faces defeat in any future war. Under this approach, Israel need not rely on Iran's compliance with any ceasefire or diplomatic agreement. Instead, Israel can feel secure because its opponents are weak. Israel also emphasizes that it must restore deterrence, which it believes failed, thus allowing the October 7 attacks. Constant use of force makes clear that Israel will defend itself.

Israel is already applying this approach in Lebanon and Syria. Although the all-out war between Israel and Hezbollah ended in 2024, Israel has kept up airstrikes and assassinations as well as maintained a limited ground presence in Lebanon that has since grown in the latest round of conflict. In areas of Syria near the Israeli border, the Israeli military has conducted raids and seized weapons, and the Israeli Air Force has hit air defenses, military infrastructure, and other targets throughout Syria.

In the future, limited Israeli operations could reduce Iranian weapons stocks, destroy command infrastructure, and kill Iranian scientists and leaders. All this can be done largely by airstrikes, resulting in relatively few Israeli casualties and avoiding the diplomatic costs and on-the-ground complexities that come with occupying territory. Israeli leaders could also calibrate the operations according to their domestic political conditions and the tolerance of international partners.

Such an approach, however, necessitates additional attacks over time as Iran rebuilds. Iran, like Hamas in planning October 7, may also adapt and develop new methods of challenging Israel that existing defenses are not designed to counter. Israel's strategy of repeated preventative strikes also risks feeding extremist narratives within Iran, discrediting moderates who might otherwise challenge the Iranian regime.

For the United States, the "wars after the war" would deepen a familiar alliance-management dilemma. Israel may prefer a strategy of repeated preventive blows to keep Iran and its proxies weak, while Gulf partners may want the United States to protect shipping and deter Iran so they can regain their status as safe havens for trade and investment. At the same time, Gulf partners likely want Washington to restrain Israel enough to avoid endless escalation that undermines trade, investment, and domestic stability.

Even if the United States tries to stay out of future rounds, Iran's perception that the United States and Israel act in lockstep increases the risk to Washington. U.S. bases, commercial networks, diplomats, shipping, and perhaps the homeland itself would remain exposed to recurring harassment and retaliation.

Finally, such conflicts create a strategic distraction for Washington. A low-level Israel-Iran conflict would keep pulling Washington back into the region through air and missile defense, maritime protection, intelligence support, cyber defense, and occasional strikes. That would mean a continuing drain on senior policymakers' attention, military assets, and munitions at a time when official U.S. strategy identifies homeland defense and deterring China as top priorities.

Daniel Byman is the director of the Warfare, Irregular Threats, and Terrorism Program at the Center for Strategic and International Studies in Washington, D.C.

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