Two months into the U.S.-Iran war, a ceasefire that President Trump declared indefinite has held — for now. Negotiations have lurched on and off, and reports emerged this week that both sides may be discussing a 14-point, single-page memorandum of understanding as the basis for a broader nuclear negotiation framework.
After the United States spent at least $25 billion on the conflict, and Iran and neighboring countries sustained thousands of casualties, the question looming over Washington and Tehran alike is whether this sudden regional war can actually be brought to a close — and whether the cargo ships and tankers bottled up in the Persian Gulf for two months or more can ever safely transit the Strait of Hormuz again.
For Stephen Mull, the veteran diplomat who led the American side of nuclear negotiations with Iran a decade ago, the answer is sobering. There are several plausible endgame scenarios, he told Storm Media in an exclusive interview this week. None of them is easy, and none offers an outcome both sides could genuinely accept.
"Honestly," he said, "I am not optimistic at all about the current situation in Iran."
The Man Who Implemented the Iran Nuclear Deal
Mull, 68, is currently Vice Provost for Global Affairs at the University of Virginia. He spent more than three decades at the U.S. Department of State, serving as Acting Under Secretary of State for Political Affairs and as U.S. Ambassador to both Lithuania and Poland.
His most consequential role came between August 2015 and August 2017, when he served as Lead Coordinator for Iran Nuclear Implementation — the official responsible for driving the U.S. government's interagency efforts to put the Joint Comprehensive Plan of Action (JCPOA) into practice. That assignment spanned the final stretch of the Obama administration's second term and the opening year of Trump's first.
In short, Mull has firsthand experience sitting across the table from Iranian negotiators on the nuclear file — experience that few American officials share.
He was in Taipei this week as a panelist at the fourth annual international forum of the Centre for Asia-Pacific Resilience and Innovation (CAPRI), participating in a session titled "Asia-Pacific Resilience Amid the Ukraine and Iran Conflicts."
Four Endgame Scenarios: Who Blinks First, or Who Bears the Pain Longer
Speaking to Storm Media on Wednesday, Mull said the conflict's trajectory hinges largely on how the Strait of Hormuz question gets resolved — specifically, whether Iran manages to extract transit fees from commercial shipping passing through the strait, or whether the United States sustains enough pressure to effectively blockade it and strangle Iran's maritime access.
"It will come down to who backs down first," he said, "or who has a higher tolerance for pain."
Mull outlined four possible scenarios for how the conflict could end.
The first is a U.S. walkaway. Facing mounting domestic political pressure, Trump could declare victory, claim credit for having degraded the bulk of Iran's military capability, and leave the Hormuz question for the rest of the world to resolve. "That wouldn't be good for the world or for the United States," Mull acknowledged, "but it's not impossible."
The second scenario involves sustained American pressure — maintaining the naval blockade and combining it with other leverage in hopes of compelling Tehran back to the negotiating table. Mull viewed this as unlikely in practice. For that strategy to work, Washington and Tehran would need at least a minimal foundation of mutual trust. By his assessment, that trust is almost entirely absent right now.
Third, a third party could step in. If Europe were to mediate and propose a diplomatic mechanism for reopening the strait — for instance, an arrangement in which transit fees are distributed not solely to Iran but shared among the Gulf states with claims over the waterway, such as the United Arab Emirates and Oman — that could offer both sides a face-saving exit. "I don't know whether Europe will step in," Mull said. "They've signaled some interest in playing a diplomatic role recently. That possibility does exist."
The fourth scenario is a return to military force, with the United States resuming strikes against Iran. Mull considered this the least likely of all. "President Trump has made clear he doesn't want to risk more American lives. He doesn't want to be dragged into yet another Middle East quagmire. So the chances of both sides returning to open conflict are limited."
On Iran's Nuclear Program, Military Force Has No Answer
That leaves unresolved the question that drove the conflict in the first place: Iran's nuclear weapons program, which both the United States and Israel cited as the core justification for military action.
Mull was unambiguous: military force cannot solve it. The only path forward is diplomatic. Before the war began, Iran had already signaled a willingness to accept certain constraints on its uranium enrichment capacity — whether by surrendering existing stockpiles or reducing enrichment levels — both of which would raise the practical threshold for weaponization.
"The only solution is to get back to the negotiating table. That's the only way," Mull said. "And any such framework must include the International Atomic Energy Agency, with inspectors on the ground inside Iran to verify compliance with whatever constraints are agreed."
Khamenei's Death Hands Power to Iran's Hardliners
Complicating all of this is a fundamental uncertainty: who is actually in charge in Tehran, and who has the authority to make decisions that stick?
Before the war, Mull explained, all major Iranian diplomatic and military decisions ultimately required sign-off from Supreme Leader Ali Khamenei. The Islamic Revolutionary Guard Corps wielded significant influence over him — but Khamenei was also open to alternative approaches, and it was his endorsement that made Iran's participation in the JCPOA negotiations possible a decade ago. He had also, at key moments, accepted centrist and pragmatist figures: Hassan Rouhani was elected president in both 2013 and 2017, outcomes Khamenei had tolerated.
That architecture of decision-making no longer exists. Khamenei was killed in a decapitation strike by U.S. and Israeli forces on the first day of the war.
"Iran was never a monolith. There were multiple factors that shaped the Supreme Leader's decisions," Mull said. "But now that Khamenei is gone, the IRGC's influence is much greater. An Iranian government shaped primarily by the IRGC is likely to be far less willing to negotiate."
It was Trump's first-term decision in May 2018 to unilaterally withdraw from the JCPOA that deepened the mutual distrust which had already made a return to talks so difficult. With Khamenei gone and the IRGC ascendant, rebuilding even the minimal trust needed to resume negotiations has become considerably harder.
"Honestly," Mull said, "I am not optimistic at all about the current situation in Iran."
