The war in Ukraine shattered a core assumption about great-power dominance: that size and military strength are enough to impose one’s will. Ukraine showed otherwise. With the right strategy, geography and resolve, a weaker state can survive and blunt – and in key respects even defeat – a much larger and stronger adversary.
The US now faces an uncomfortable parallel. The war with Iran is exposing similar limits to American power.
For decades, US grand strategy has rested on the belief that America’s unmatched military capabilities enabled it to uphold global stability and shape outcomes across entire regions.
After the failures in Iraq and Afghanistan, and the mess in Iran, many Americans have reached a stark conclusion: the cost of that primacy is no longer sustainable, and no longer serves their interests.
A strategy that depends on military dominance everywhere, at all times, inevitably means being at war somewhere, all the time.
America’s endless wars are not an accident, they are the product of this approach. And if there is one rare point of agreement in an increasingly divided country, it is this: Americans are tired of war.
Yet, despite a war-weary public, mounting economic strain and politicians who promise to end endless wars, inertia – and powerful economic interests tied to war – have mostly kept this approach intact.
The question now being asked is whether Trump’s debacle in Iran will finally break this pattern. Early signs suggest its repercussions may exceed even those of George W Bush’s war of choice in Iraq.
The US actually won the Iraq war in under three weeks. Its military dominance was never in doubt. But it lost the peace, failing to stabilise the country once the insurgency took hold.
In Iran, however, the US hasn’t even won the military phase of the conflict, despite facing a far weaker conventional force.
Iran has leveraged geography and asymmetric tactics to blunt American power and inflict a strategic setback. Even more striking, early claims that US air strikes had significantly degraded Iran’s drone and missile capabilities now appear overstated.
The lesson is clear: control of the skies does not guarantee control of outcomes, and without the will to deploy ground forces – and without the ability to translate airpower into decisive results – US military hegemony begins to look increasingly hollow.
Meanwhile, as some experts have pointed out, even though the Iraq war ultimately failed, it did achieve its immediate goal: overthrowing the regime of Saddam Hussein. In Iran, the opposite appears to have happened. Rather than damaging the regime, the war has likely strengthened it and reinforced hard-line control, at a time when it was looking weakened by domestic protests.
Stephen Walt, a Harvard professor, notes that while the Iraq war destabilised the region, its global repercussions were relatively contained. It did not trigger an oil crisis, widespread food shortages or major supply chain disruptions. Iran, by contrast, has already sent energy markets into turmoil, driving oil and gas prices to record highs and triggering energy emergencies in multiple countries.
It may also have fundamentally reshaped the geopolitical landscape of the Persian Gulf for years to come.
Military primacy for the US was always a choice, not a necessity. The Iran war suggests it may no longer even be a viable one. A strategy built on escalation dominance falters when escalation itself becomes too risky to use. One that relies on decisive victories breaks down when enemies can consistently push for stalemates.
What emerges instead is arguably a different kind of global order: one not defined by dominance but by mutual denial. In this world, great powers cannot simply impose their will, and smaller states can resist them at tolerable costs. The result is not chaos, but constraint.
The most likely outcome of the current US-Iran stand-off is neither a deal nor a return to active war, but a prolonged, uneasy equilibrium. That, too, is a sign of the times.
The Trump White House may walk away from negotiations, but it is unlikely to re-enter a full-scale war. Not because the US lacks the capability, but because it lacks the strategic freedom to use it.
For countries that largely depend on US protection, this should be a wake-up call.
This does not mean alliances will collapse, but it does mean they will change. Countries will hedge more, diversify their security relationships and place greater emphasis on regional balances of power rather than reliance on a single guarantor.
In that sense, Iran is not a rupture so much as a speeding up of a trend already well underway.
Iraq and Afghanistan exposed the limits of Western occupation and regime change. Ukraine exposed the vulnerability of large conventional forces. Iran now exposes the limits of military coercion itself.
As my colleague Monica Toft argues, other smaller powers don’t need a vital waterway like the Strait of Hormuz to effectively constrain a superpower the way Iran has done. The shaping of terrain and geography – like in Ukraine – is sufficient. In short: Iran’s strategy is replicable elsewhere.
These conflicts, taken together, point to a more multipolar world – not because new great powers have risen but because existing ones can no longer dominate as they once did.
The danger for the US is not irrelevance. It’s that it continues to pursue a strategy designed for a world that no longer exists. The same is true for countries, like the UK, that have largely chosen to rely on American military dominance. American hegemony promised control, but the Iran war revealed the limitations of American power.
In the gap between promise and reality lies the likely end of an era. The winners will ultimately be those who adjust.
Trita Parsi is an Iranian-born foreign policy analyst, writer and the co-founder and executive vice president of the Washington-based Quincy Institute for Responsible Statecraft. He has authored four books on US foreign policy in the Middle East, with a particular focus on Iran and Israel.