President Donald Trump’s conflict with Iran has become a political liability for his administration. Since the last U.S. strikes on Iran fell on Sept. 8, Trump has publicly ruled out attacking Iran before the November midterm elections—and promised to end the conflict after them.

Then, rumblings grew that U.S. and Israeli military planners had reportedly drawn up new strike options against Iran, including the possible use of the largest non-nuclear weapon in the American arsenal: the GBU-43/B, also dubbed “the Mother of All Bombs”.

The targets purportedly would be Iran’s nuclear facilities and energy infrastructure, though there are doubts about whether the bomb could penetrate Iran’s most deeply buried sites. According to these reports, Trump apparently is seeking a strike he could present as a military victory and then end the war without appearing to back down.

But such an approach risks triggering a far wider war than Washington intends. Tehran remains unlikely to let Washington end the conflict quickly and, fearing a potential attack from the U.S., could itself strike first. Either scenario could lead to a new round of fighting far more destructive than the last.

Before the mother of all bombs Reports of military plans involving “the mother of all bombs” came against the backdrop of two other worrying developments. First, Iran has been escalating its naval attacks, likely in response to increased flows through the Strait of Hormuz. Notably, two UAE-owned cargo ships, the GFS Pride and the Cape Dao, were struck in the Strait as part of this sharp uptick.

Secondly, diplomatic efforts appear to have hit a wall. In late September, Trump rejected the proposal Tehran had put forward on the sidelines of the U.N. General Assembly: an end to fighting on all fronts, including Lebanon; the lifting of the U.S. naval blockade and oil sanctions; the release of some of Iran’s frozen assets; and the reopening of Hormuz within seven days. Instead, Washington insists that Iran must take steps regarding its nuclear program as part of the package, something Iranian leaders say they will only do at a later stage.

The timing of any U.S.-Israeli attack remains uncertain. While Trump has said he will not resume attacks before the midterms, Israel held its election on Oct. 27, a week earlier, and Prime Minister Benjamin Netanyahu had reportedly sought renewed fighting before both elections.

American and Israeli objectives may differ, of course. Trump appears to want something he can portray as a spectacular military victory without having to undergo another prolonged war, while Netanyahu’s rhetoric about “finishing the job” suggests more ambitious goals, potentially including toppling the Islamic Republic. Tehran seems to be preparing for either scenario with its own response: a prolonged, region-wide war designed to impose devastating economic costs.

Denying Trump a short war The dominant perspective in Tehran is that the next war must be fought in a way that makes it so costly that a future U.S. president would not contemplate another. Hossein Mohebbi, a spokesperson for the Islamic Revolutionary Guard Corps (IRGC), said in late September that Iran “will not stop until we have driven the United States out of the region, punished the aggressor, and established permanent deterrence so that no one will dare attack Iran.”That logic, should it prevail, rules out a symbolic, tit-for-tat exchange.

In Tehran’s view, a limited American strike on Pickaxe Mountain, the fortified nuclear site near Natanz that Trump has repeatedly evoked, followed by a limited Iranian response, would send Washington precisely the wrong message: that it can attack Iran’s nuclear facilities, domestic political gain, and pay a limited, acceptable cost. Iranian officials have therefore warned that even a symbolic, non-lethal strike would trigger a broad response, denying Trump the quick exit he may have asked of his war planners.

Under this scenario, Iran would target regional energy and economic infrastructure. “In a region where we cannot sell oil, no one will sell oil,” Ghalibaf has warned. The UAE is particularly exposed: Mohsen Rezaei, secretary of the Supreme National Security Council, has accused it of oil “smuggling” in cahoots with U.S. Central Command (CENTCOM). Rezaei also identified new potential targets: undersea cables, data centers, and AI infrastructure in the region, which he claims are worth “more than $2 trillion.”

Ghalibaf subsequently extended the threat to regional governments and investors, threatening that anyone providing “funding, equity, land, or energy” to AI companies that “facilitate military aggression” against Iran “will face coercive action.”If raising the cost of war is the first instrument in Iran’s calculus, duration is the second. Ali Balali, an adviser to the IRGC’s Aerospace Force commander, suggested Iran would conserve its arsenal in preparation for a prolonged confrontation, rather than expend it early. Two days later, Iranian Army spokesperson Mohammad Akraminia argued that the enemy’s weak point is a prolonged war.

Timing is a third dimension in Iranian thinking. Iranian military officials have increasingly mentioned the possibility of striking first, preemptively. Akraminia stated that if Iran were to conclude that an attack by the U.S. and/or Israel is imminent, “we will certainly engage in preemptive warfare.”Mehdi Mohammadi, strategic affairs adviser to Parliament Speaker Mohammad Bagher Ghalibaf, went further, arguing that a successful strategy requires not only striking first but also delivering a decisive blow capable of “changing the balance.”There is thus at least the possibility that Iran might move early, and then fight long.

That could occur due to miscalculation resulting from ambiguous American and Israeli signals: leaked strike plans, carrier and amphibious deployments, and aircraft approaching but not entering Iranian airspace. Military experts in Iran see this pattern as an effort to normalize military activity and regain the element of surprise. Tehran could thus mistake military signaling for an imminent attack and strike preemptively, even though it may not want another round of war.

The fourth element concerns the range of those Tehran would hold responsible in the event of an attack. On Oct. 5 Ali Abdollahi, chief of staff of Iran’s armed forces, declared that if the United States acted against Iran “directly or indirectly through Israel,” Iranian forces would retaliate against the United States. The warning carries more weight in the wake of Trump’s decision to openly back Netanyahu ahead of Israel’s election. Indeed, some in Tehran interpreted this as a signal that Washington would allow Israel to strike Iran after the midterms. As a result, Tehran has made clear that even were Israel to carry out the attack on its own, U.S. forces and assets in the region would face retaliation.

Widening the map This interpretation suggests that the scope of Iran’s response to a U.S. strike likely would be far wider. Its conduct in Hormuz since late September offers a preview of how it could broaden the conflict. When the UAE, backed by CENTCOM, kept oil moving through a southern corridor along the Omani coast, the IRGC shifted its attacks from small shuttle tankers to supertankers and stated that vessels using the “illegal corridor” would be “pursued and interdicted across the region.”Strikes followed off the UAE coast and near Qatar. An escalation in the region could drive Iran to go after vital energy and other infrastructure across the Gulf.

Iran’s regional partners also could widen the conflict, although Tehran does not fully control their actions. In Yemen, the Houthis have already opened a second maritime front in the Red Sea, threatening shipping and increasing pressure on Saudi Arabia. In Iraq, Kataib Sayyid al-Shuhada, an Iran-backed militia, has threatened to fight if Iran faced an existential threat. The conflict could also extend to Europe through indirect operations.

There may already have been attempts in this vein: British Prime Minister Andy Burnham said a suspected September plot near RAF Fairford, a base used by U.S. bombers, was “almost certainly” directed by the IRGC. Tehran denies involvement, but the incident raises the prospect of covert operations against American military assets beyond the Middle East.

Tehran is also preparing for the possibility of a ground operation inside Iran. According to Iranian Army Ground Forces commander Ali Jahanshahi, more than 50 units are deployed along the borders, from the northwest to the Makran coast, and abandoned airfields have been identified as potential enemy landing sites. Iranian security forces have also conducted preemptive operations against Baluch armed groups in the southeast and launched drone and artillery strikes in Kurdish border areas amid concerns that they could open an internal front during an external attack.

A war meant to be the last Both the U.S. and Iran run the risk of serious misjudgment. The U.S. may believe it can be master of the scope and duration of a war, only to find that Iran holds the key. This power means Iran need not let the conflict end quickly or painlessly.

For its part, Tehran—which survived the fierce exchanges that began in late February, continued through April, and have since become more regionalized—may be convinced that a wider conflict this time again would establish lasting deterrence. But conditions that made this strategy relatively effective in the past have changed, partly because of Iran’s own actions. The more Tehran expands its targets, the more it risks turning neighbors that sought to stay out of the conflict into supporters of its defeat. Saudi Arabia and the UAE have reportedly agreed to coordinate their military support on behalf of anti-Houthi forces in Yemen, while Egyptian President Abdel Fattah el-Sisi has offered to help defend Saudi Arabia against Houthi attacks.

For the Gulf monarchies, the stakes are becoming existential: either Iran’s leverage is broken, or their access to world markets will remain dependent on Iranian restraint.

In this way, a war intended to deter future American attacks could instead strengthen a regional consensus that Iran must be dealt a serious blow rather than accommodated or bargained with.

Ultimately, diplomacy remains the only way to prevent the gap between American and Iranian perceptions and risk calculus from triggering another, potentially even more costly round of confrontation. Without it, Washington could launch a limited strike expecting a quick exit, or Tehran could strike first fearing an imminent attack. Either scenario could trigger a prolonged regional war that the U.S. wishes to avoid and a growing alliance against the Islamic Republic for which Iran would pay a price.