There is a particular kind of strategic embarrassment that comes not from being defeated in battle, but from discovering that your entire operational theory was wrong from the start. The United States and Israel launched their air campaign against Iran with a theory of victory that had one fatal flaw: it assumed a centralised enemy. What they found instead was the Mosaic Defence — and three weeks in, that distinction is defining the outcome.
The question is no longer whether the campaign has underperformed. The question is what Washington and Tel Aviv intend to do about a problem they cannot bomb their way out of.
The architecture that cannot be decapitated
Iran’s Islamic Revolutionary Guard Corps (IRGC) did not stumble into resilience. As early as last June — months before the first strike — Tehran made the decision to disperse its military capabilities across 31 fully autonomous provincial units and delegate authority for weapons use to local commanders. The result: no single nerve centre to sever, no command hierarchy whose decapitation produces paralysis, no communications backbone whose disruption cascades into collapse. Each unit carries pre-authorised orders, its own targeting logic, and the mandate to continue operations indefinitely.
This is the operational core of the Mosaic Defence, not redundancy in the conventional military sense, but genuine distributed agency. The units communicate with Tehran and with each other, but they do not depend on daily instructions to function. The doctrine was built by people who understand, from lived experience, what it means to fight without reliable command lines. They did exactly that during the Iran–Iraq War, when Saddam’s air force and Western intelligence support made centralised command a liability. The generation now running the IRGC didn’t inherit this philosophy. They wrote it.
“The reality is that the U.S. underestimated the task and, as of about two weeks ago, lost the initiative to Iran.”
Sir Alex Younger, Former Director, MI6 — The Economist, March 25, 2026
Sir Alex Younger, former head of MI6, confirmed as much in his interview with The Economist. The Mosaic Defence, in his assessment, gave Iran “significant extra resilience” against a campaign he nonetheless describes as “incredibly powerful.” That is a quiet but devastating verdict from a man who spent his career fighting the IRGC and explicitly says he shed no tears for Khamenei.
The men who built the machine
Four figures are likely to shape Iran’s conduct in the coming weeks, and they share a biographical fact that matters more than their ideological labels: all emerged from the generation formed by the Iran–Iraq War.
Mohsen Rezaei commanded the IRGC general staff at 27 and directed it through the entirety of the war, helping to shape the operational thinking that would later evolve into today’s decentralised model. He remains widely seen as a key strategic voice behind the current campaign. Mohammad Baqer Ghalibaf, now Speaker of Parliament, was also formed by that conflict, which continues to inform his strategic outlook. Alireza Arafi provides part of the system’s ideological and institutional grounding within Iran’s clerical establishment. And Abbas Araghchi — Foreign Minister, veteran of the same wartime generation, and a central figure in the 2015 nuclear negotiations — is an experienced interlocutor with the West who understands both its constraints and its red lines.
None of these men are incapable of negotiation. But none are likely to negotiate from a position they perceive as weakness. The reported 15-point Witkoff plan, circulated through intermediaries, asks Iran to accept terms more consistent with defeat than compromise. For a leadership cohort shaped by an eight-year war marked by chemical weapons use and external backing for Baghdad, such terms were unlikely to gain traction.
Horizontal escalation: the strategy that “sort of worked”
Iran’s response to the air campaign has unfolded across three interlocking layers. Alex Younger described the first as “horizontal escalation”, targeting assets across a widening geographic arc, including states throughout the Gulf. Initially assessed as irrational, this approach has proven more effective than expected. By expanding the political and economic perimeter of the conflict, Tehran has imposed indirect costs that extend well beyond the battlefield.
The second layer is the energy war. Iran has maintained the Strait of Hormuz under credible threat; a transit route for roughly 20 million barrels of oil per day, or around one-fifth of global seaborne supply. Alternative pipeline capacity is limited and estimated to cover only a fraction of that volume. In the weeks following the initial strikes, oil prices have surged sharply, reflecting both physical risk and market perception. Even with significantly reduced drone capacity, Tehran retains the ability to deter commercial shipping, not by targeting naval assets directly, but by raising the risk threshold for tanker operators and insurers. The result is upward pressure on energy prices, translating into domestic political strain for governments exposed to those markets.
The third layer is time itself. Iran frames the conflict as existential; the United States entered it as a matter of choice. As Younger noted, this asymmetry confers greater staying power on Tehran. With polling suggesting a majority of American public opinion opposed to military involvement, that endurance, combined with the structural resilience of the Mosaic Defence, increasingly shifts the strategic balance over time, regardless of battlefield attrition claims.
The internal fractures — on both sides
Conflicts are decided as much by internal coherence as by firepower, and neither side in this war is monolithic. Within the Israeli establishment, Benjamin Netanyahu and Mossad appear to favour more ambitious objectives, including regime change, while the military has generally leaned toward more limited and incremental aims. Assessments in Washington that Iran might prove vulnerable to internal unrest, reportedly informed in part by Israeli intelligence, have so far not been borne out. No large-scale protests have materialised, and the original theory of victory increasingly appears to have been set aside rather than formally revised.
Within Iran, there are also indications of divergence between the Islamic Revolutionary Guard Corps and the regular military. The latter has signalled a preference for keeping the confrontation contained, focusing on Israeli and American targets while avoiding actions that would decisively disrupt traffic through the Strait of Hormuz. The IRGC, by contrast, appears more willing to widen the conflict, including the possibility of targeting Gulf states and sustaining pressure on global energy flows. If that logic prevails, the conflict could expand into territory with unpredictable consequences for regional order and global markets.
Speculation around succession has also intensified. Mojtaba Khamenei is widely seen as a potential successor to Ali Khamenei, and any transition is likely to reinforce rather than dilute the system’s underlying logic. The Mosaic Defence does not depend on a single leader; it rests on a structure designed for continuity. Recent events have offered a live test of that design. So far, the system has passed it.
The internal fractures — on both sides
Conflicts are decided as much by internal coherence as by firepower, and neither side in this war is monolithic. Within the Israeli establishment, Benjamin Netanyahu and Mossad appear to favour more ambitious objectives, including regime change, while the military has generally leaned toward more limited and incremental aims. Assessments in Washington that Iran might prove vulnerable to internal unrest, reportedly informed in part by Israeli intelligence, have so far not been borne out. No large-scale protests have materialised, and the original theory of victory increasingly appears to have been set aside rather than formally revised.
Within Iran, there are also indications of divergence between the Islamic Revolutionary Guard Corps and the regular military. The latter has signalled a preference for keeping the confrontation contained, focusing on Israeli and American targets while avoiding actions that would decisively disrupt traffic through the Strait of Hormuz. The IRGC, by contrast, appears more willing to widen the conflict, including the possibility of targeting Gulf states and sustaining pressure on global energy flows. If that logic prevails, the conflict could expand into territory with unpredictable consequences for regional order and global markets.
Speculation around succession has also intensified. Mojtaba Khamenei is widely seen as a potential successor to Ali Khamenei, and any transition is likely to reinforce rather than dilute the system’s underlying logic. The Mosaic Defence does not depend on a single leader; it rests on a structure designed for continuity. Recent events have offered a live test of that design. So far, the system has passed it.
What a non-defeat looks like
The most probable near-term outcome is what observers often describe as “constructive ambiguity”: Donald Trump declares victory in terms domestic audiences can accept, military operations gradually de-escalate without a formal agreement, and Iran emerges weakened but intact, still capable of rebuilding its deterrent over time. A negotiated settlement remains theoretically achievable, but only on terms that allow the Iranian leadership to claim it was not coerced. Abbas Araghchi’s response to the Witkoff plan, that “sending messages through intermediaries is not a negotiation,” signals where Tehran’s floor is.
A deal resembling the Joint Comprehensive Plan of Action, with additional constraints on missiles and regional activity, might still be within reach; a deal resembling a surrender document is not. The Mosaic Defence has done what it was designed to do: it has shifted a conventionally superior military campaign toward a war of attrition that the initiating side may struggle to sustain indefinitely. At the same time, this should not obscure the real costs Iran is absorbing. Its economy is under severe strain, its energy sector under sustained pressure from the conflict, and its population facing repeated waves of unrest met with harsh repression by the Islamic Revolutionary Guard Corps. Resilience and legitimacy are not the same thing, and Tehran is acutely aware of that distinction.
Alex Younger’s assessment carries the weight of experience: Iran has played “a weak hand pretty well.” The deeper problem for Washington is structural. A doctrine built on distributed agency and pre-authorised decision-making does not disappear when the conflict subsides; it adapts, absorbs lessons, and persists. The Mosaic Defence will remain in place for the next confrontation, more battle-tested, more credible, and reinforced by the precedent that it worked.