[U.S.–Iran War] Iran Signals “Resistance Doctrine” With Mojtaba as Supreme Leader—A Figure Trump Once Called “Unacceptable”

Iran Signals Hard-Line Shift and Willingness to Resist
Potential Reignition of Sunni–Shia Tensions Across the Middle East
Momentum Builds Toward Protracted War, Testing Both Nations’ Endurance

Iran’s constitutional body has selected a new Supreme Leader, signaling a transition to a new governing framework. Mojtaba Khamenei—the son of the late Supreme Leader and widely regarded as a hard-liner—has assumed the role, sending a political message that Tehran is prepared to accept confrontation with the United States rather than pursue negotiations. At the same time, Iran expanded the scope of its military strikes to Gulf states, driving tensions higher across the Middle East, while the United States moved to reinforce military personnel and discuss additional funding in preparation for a prolonged conflict.

Effort to Minimize Leadership Vacuum

According to Iran’s state-run Tasnim News Agency on the 8th, Mojtaba—the younger son of Supreme Leader Ayatollah Ali Khamenei, who was killed in airstrikes carried out by the United States and Israel—has been selected as his successor. The outlet reported that “following the martyrdom of Ayatollah Ali Khamenei, who led Iran for 37 years after the death of Imam Khomeini in 1989, the Assembly of Experts elected Ayatollah Mojtaba Khamenei as the third leader of the Islamic Revolution.” The decision came just ten days after the death of the elder Khamenei, a move analysts say reflects Tehran’s determination to minimize any leadership vacuum during wartime.

International media have suggested that the Islamic Revolutionary Guard Corps (IRGC) may have played a decisive role in the succession process. Reuters described Mojtaba’s elevation as “a signal that Iran’s hard-liners continue to hold formidable power in Tehran.” The New York Times similarly reported that “Mojtaba’s appointment as Supreme Leader sends a message that hard-line factions linked to the Revolutionary Guard remain in control and that little change is likely in the near term.” In other words, Tehran has signaled that it intends to maintain its hard-line posture rather than leave the door open to negotiations with Washington.

In practice, Mojtaba had already exercised substantial influence within Iran’s power structure even while his father was alive. He served as the de facto leader of the Basij militia under the IRGC—often described as a “government above the government”—and played a key role in suppressing anti-government protests. At the same time, he wielded influence over the operations of key state assets such as the secretive state conglomerate Setad and the state broadcaster IRIB, earning a reputation as a figure who held the “sword,” the “money,” and the “media” simultaneously. His career path also mirrors that of Iran’s political elite. Mojtaba was educated at Tehran’s Alavi institutions, known for producing political and religious elites, and at the Qom seminary, and he also served in the Iran–Iraq War from 1987 to 1988.

Tehran’s decision also carries a strong political message directed at Washington. U.S. President Donald Trump had previously voiced explicit opposition to the prospect of Mojtaba succeeding his father. “Khamenei’s son is unacceptable to me,” Trump said, expressing strong resistance, and in a phone interview with Axios he described Mojtaba as “lightweight.” Nevertheless, Iran moved forward with Mojtaba’s appointment despite Trump’s objections, a decision widely interpreted in diplomatic circles as a declaration that Tehran has no intention of yielding to U.S. pressure.

Rising Possibility of Gulf States’ Military Response

Iran broadened the battlefield during its military response to the United States and Israel, extending attacks to neighboring Middle Eastern countries. Drone and missile strikes targeted U.S. military facilities and assets in Gulf states including Bahrain, Saudi Arabia, and the United Arab Emirates. Iran emphasized that the attacks were not directed at the Gulf countries themselves, yet the spread of damage to civilian infrastructure—including desalination plants, airports, and university buildings—triggered mounting international criticism. As the conflict escalated, its nature also began shifting beyond a bilateral Israel–Iran confrontation toward a broader regional conflict.

Amid this escalating trajectory, Iran’s leadership briefly attempted to send a message of de-escalation. Iranian President Masoud Pezeshkian announced during a state television address on the 7th that Tehran would suspend attacks, offering an apology to Gulf states. “The interim leadership committee has approved a plan to halt attacks on neighboring countries as long as those countries do not attack Iran,” he said. He added that “we have no hostility toward the countries of the region,” signaling that Tehran did not seek an expansion of the conflict. Yet the very next day Pezeshkian reversed course, declaring that “if Iran’s enemies attempt to use any country to attack or invade our territory, we will have no choice but to respond.”

Following that statement, the scope of Iranian strikes expanded rapidly. A U.S. helicopter base in Kuwait was hit by drone and ballistic missile attacks, damaging training and maintenance facilities as well as fuel tanks, while Kuwait International Airport was also struck, leaving two border guards dead. The UAE Ministry of Defense later announced that the death toll from Iranian attacks had risen to four. Iran’s Revolutionary Guard Corps acknowledged launching hours-long air assaults on Israeli targets in Tel Aviv and Haifa as well as U.S. bases in Kuwait. Tehran also announced that next-generation missiles had been deployed to strike multiple Israeli cities and Jordan’s Al-Azraq Air Base.

Some observers have warned that the confrontation could spread into sectarian conflict. Most Gulf states are governed by Sunni leadership, while Iran operates under a Shiite theocratic system. The longstanding rivalry between Saudi Arabia and Iran has also been rooted in this sectarian divide. If Iranian attacks continue, analysts warn that Gulf states could launch military responses, potentially transforming the conflict into a broader religious war between Shiite and Sunni blocs. Majed Al-Ansari, spokesperson for Qatar’s foreign ministry, issued a strong warning during a press conference on the 8th, stating that “Iran has already crossed every red line.” His remarks were widely interpreted as a signal that Gulf states—until now focused primarily on diplomatic mediation—may be preparing for a military response.

U.S. Faces Dual Challenge: War Costs, Rising Oil Prices

The United States is also moving as though it expects a prolonged military campaign in the Middle East. Politico reported on the 5th that U.S. Central Command had requested additional military intelligence officers to support operations related to Iran for at least 100 days. In a joint press conference with Defense Secretary Pete Hegseth, Central Command chief Brad Cooper said he had been assigned “additional missions to neutralize Iran’s ballistic missile industrial base,” adding that the objective was “to completely destroy its future reconstruction capability.” The remarks indicate that Washington has set a strategic objective of weakening Iran’s military capacity over the long term.

The challenge, however, lies in the immense financial burden of a prolonged war. A study by the Center for Strategic and International Studies (CSIS) estimated that the Trump administration spent $3.7 billion during the first 100 hours after launching Operation Epic Fury on the 28th of last month. If the war continues, analysts estimate that an additional $890 million per day could be required. The total would also need to account for $3.1 billion in ammunition replenishment costs and $350 million in equipment losses and infrastructure repairs. CSIS warned that “interception operations at the current pace are difficult to sustain for more than a few weeks,” adding that the reliance on expensive missiles to intercept low-cost drones could rapidly escalate the financial burden.

President Trump has proposed using tariff revenues imposed globally as a source of war funding, but the plan encountered obstacles after the U.S. Supreme Court ruled the reciprocal tariffs unconstitutional. Meanwhile, the 10 percent global tariff introduced as a replacement measure has also become embroiled in constitutional disputes, prompting a lawsuit joined by 24 of the 50 U.S. states. At the same time, the U.S. Court of International Trade ordered the government to begin refund procedures for reciprocal tariffs. The ruling raises the possibility that Washington could face the additional financial burden of tariff reimbursements even before securing funds for wartime expenditures.

Ultimately, sustaining a prolonged military campaign will require congressional approval for additional funding, a process that also faces significant political hurdles. The Department of Defense has prepared a supplementary budget request of up to $50 billion to replenish depleted weapons stockpiles, but Democrats have maintained opposition on the grounds that the administration has not sufficiently disclosed its plans for how the military spending would be used. Politico reported that a congressional compromise could still emerge if the funding package becomes linked to aid for Ukraine. Meanwhile, the White House has begun examining measures to stabilize energy prices, wary that a prolonged war could drive global oil prices higher and trigger broader economic repercussions.