Here’s how Iran could become a “forever war”

The Trump administration’s end goals for the war in Iran, never particularly well-defined to begin with, appear to be narrowing.

When will that be? Trump says he will “feel it in my bones.”

This should have been obvious from the start. Air campaigns almost never overthrow regimes and there’s little appetite in Washington to send in ground troops. Some officials in the US and Israel still optimistically hope that the conditions for regime change may have been created. Some point to the example of Serbian dictator Slobodan Milošević, whose regime survived a NATO air campaign in 1999 but, badly weakened, collapsed in a popular uprising about a year later. Ethnic minorities like the Kurds could also take advantage of Tehran’s weakness to push for greater autonomy, fragmenting the government’s control if not overthrowing it entirely.

But for now, those are theoretical scenarios. Trump has reportedly been briefed by advisers in recent days that Iran’s ruling regime is not close to collapse, despite the beating it has taken, and is likely to emerge from this war weaker, but even more hardline.

Defenders of the US-Israeli strategy argue it’s still worth it: that the destruction of much of Iran’s missile program, navy, air defenses, and nuclear program will make it much harder for the regime to project power across the region.

The problem is what happens when the war is over. Military and nuclear capabilities can be set back, but they can also be rebuilt. Trump himself has cited the threat from an Iranian nuclear program he claimed to have “obliterated” less than a year ago as (accurately or not) a major reason he launched an even larger war now.

Worse, the Islamic Republic that remains could have a higher tolerance for risk and even more motivation to impose future costs on its adversaries. If it retains its stockpile of highly enriched uranium, Iran will have more incentive than ever to rush toward a nuclear bomb rather than engage in yet more fruitless negotiations. It will almost certainly attempt to rebuild its ballistic missile program. Its ability to disrupt oil traffic through the Strait of Hormuz has revealed a dangerous new capability that it will seek to bolster.

“Iran doesn’t want to become one of these countries in which the US and Israel take military action based on a Google Calendar reminder every six months,” said Ali Vaez, head of the Iran program at the international crisis group. “It believes that that is death by 1000 cuts.”

All of this could trigger yet another military response from Israel and the US, who would fear losing their current dominance over a weakened Iran, particularly if Iran appeared to be reviving its damaged nuclear program.

That leaves us with an uncomfortably plausible scenario: That the war in Iran is only the first of many.

In the United States, the prospect of an indefinite on-again, off-again war with Iran is likely to be troubling to Trump’s critics on the left and right alike. The White House is already pushing back against the idea the country is entering another “forever war” with murky goals and an indefinite timeframe.

In Israel, though, the idea of a long-running episodic war against regional threats is already well established. Israel’s defense minister, Israel Katz, has already suggested that after the war, they may switch to what he calls a “policy of enforcement.”

There’s a more colloquial name for this strategy: “mowing the grass.”

The phrase originally comes from an influential article by the Israeli defense analysts Efraim Inbar and Eitan Shamir published shortly after Israel’s six-week war in Gaza in 2014. The article argued that rather than becoming embroiled in a draining, long-term, Iraq-style counterinsurgency campaign in hopes of eliminating Hamas, Israel could keep the group off balance with periodic short engagements. “Israel simply needs to ‘mow the grass’ once in a while in order to degrade enemy capabilities,” they wrote.

The model collapsed spectacularly on October 7, 2023, when the military was caught off guard by Hamas’s surprise attacks in southern Israel, which were followed by exactly the sort of costly long-term war the strategy had been intended to avoid.

In an interview with Vox this week, Shamir, a former adviser in the Israeli prime minister’s office now with the Begin-Sadat Center for Strategic Studies, argued this was not because the strategy was flawed, but because it was poorly implemented, with the Israeli government failing to monitor Hamas’s growing capabilities. “What we had was lousy mowing the grass,” he said.

Israel has also applied “mowing the grass” thinking beyond the Palestinian territories, for instance in the strikes against Iranian and Hezbollah targets in Syria known as the “campaign between the wars” from around 2022 to 2024. Following October 7, there was a dramatic uptick in Israeli strikes against Iranian-backed groups in Syria, Lebanon, and Yemen — a kind of regional mowing the grass strategy.

The difference this time is that a variation of the strategy is being applied against the Iranian state itself, rather than a proxy group operation on another country’s soil.

Shamir said that while regime change is still the dream scenario for Israeli Prime Minister Benjamin Netanyahu, he’s happy to settle for the damage the US and Israel are inflicting now, and will continue the campaign for as long as Trump will allow it.

“Every day that passes that Trump is not putting a stop to this is pure profit” for Israel, Shamir said. “Every day you’re degrading more and more capabilities.

The “mowing the grass” model is likely a disturbing prospect for Americans opposed to the war, but it also has critics among Iran hawks, who hope the current war will lead to an overthrow of the regime and a democratic future for the country.

“It’s a costly option and one I would say it’s one that we should not settle for,” said Behnam Taleblu, a senior fellow at the Foundation for the Defense of Democracies, a think tank advocating regime change. “The longer you stay in a state of violence the less likely you are to retain the population that you need to push for a better post-Islamic Republic future for Iran.”

As Shamir notes, the limiting factor of this strategy is the White House’s tolerance for war.

For years, US presidents — to the Israeli government’s enormous frustration —rebuffed Israel’s requests to take direct action against Iran. Now, Trump has broken precedent: The US and Israel are directly striking Iran and —for the first time — the two countries’ militaries are fighting side by side. Israel is clearly anxious to take full advantage of this moment in Iran as well as Lebanon. But the moment may not last.

Trump has indicated that he is surprised by both the ferocity of Iran’s retaliation against the Arab Gulf states and the impact the conflict is having on energy prices. He is now considering risky options to reopen the Strait of Hormuz; a shift from a president who has so far repeatedly defied critics who warned his military engagements would lead to quagmires.

Even if Israel is willing to do this all again in six months, it’s far from certain that Trump would be up for it, not to mention another president. “In the long run, your politics don’t look good for Israel,” Shamir said.

But even a future American leader who opposes the current war, or who supported prior rapprochement efforts with Iran, might find themselves caught in the logic of “mowing the grass.” No president has been comfortable with the idea of a nuclear Iran; even if they blame the prior administration for inflaming tensions and cutting off diplomacy, they may find themselves facing pressure to act again if the Islamic Republic looks like they’re ramping up a weapons program.

For hawks in both the US and Israel, however, an Iran kept indefinitely off-balance and unable to effectively defend itself from future reprisals might be the next best thing to regime change. That suggests the outcome of this war may simply set the stage for the next one.