The outcome of the current Iran war is still in doubt, but one consequence is already becoming clear: it has weakened America’s capacity to project power. Many are asking who won. The more important question may be what the war has cost.

The Gulf’s geo-economic position means that this war, short and small by historic standards, will have long-lasting global effects. One of the most important concerns the future US capacity to project power. A quick look at the balance sheet helps identify how that may play out.

Gains and losses

The losses, of course, include the impact on nature, on the people of Iran and on the Gulf states. The poor in other regions will suffer as food insecurity rises. On the sidelines, Putin’s Russia has benefitted by being able to sell more oil, but its support for Iran will cost it friends and investment capital from the Gulf. Meanwhile, Ukraine has also benefitted because several Gulf states want its drones and technical support.

Of the main combatants, Israel gained some freedom of action in Gaza and Lebanon. But it is piling up problems for the future, just as it did when it escalated in Lebanon in the early 1980s. Iran has gained a kind of win by not losing while, conversely, the US loses by not winning. And this will have a serious impact on its capacity to project power in the coming years.

There are two aspects to this. One is material and concerns the ability to coerce; the other is non-material and concerns influence. The material aspect would be significant even if the war had been more successful.

The US struck over 13 000 targets in Iran in 39 days of fighting. It used up more than half its stealth cruise missiles. At current rates of production, replacing them will take five to six years. It used as many Tomahawk cruise missiles as it produced in 10 years and about two years’ worth of Patriot interceptor missiles.

The US still has huge capacity to use force, though it may have to use it differently.

Not surprisingly, some anxiety has been expressed that the US military capacity to respond to another crisis has been reduced. Equally unsurprisingly, top-level military leaders and civilian officials assure allies and adversaries alike that the US can still handle all contingencies and project its power at will.

The amount of weaponry used is emphasised by critics because they see that the US has gained nothing by it. But even if the victory the President has frequently proclaimed were real, the weapons would still have been used. If reduced weapon stockpiles cause a problem, it is a problem regardless of the war’s outcome.

Both the concern and the complacency are overstated. The US still has huge capacity to use force, though it may have to use it differently if the President sees a new need or opportunity for military action. It remains a military superpower, but one with thinner margins, more difficult trade-offs and less freedom to respond simultaneously to crises in different regions.

The non-material aspect is even more significant. Influence takes many forms — political, economic and cultural. One source of political influence is military superiority. States that are seen as overwhelmingly powerful often gain friends and persuade adversaries to give way. The Gulf war, however, has exposed the limits of that logic.

President Trump is not wrong when he praises US military prowess. But his boasts during the Iran War have only drawn attention to the tightly limited utility of all that force. Iran’s military capacity has been damaged, and the economy is in terrible condition, but the regime is still in power, with a harder line and tighter control. When the ceasefire started, it still had 70 per cent of its pre-war stock of missiles and has doubtless produced more by now.

The US is no closer than it was the day before the war to getting Iran’s enriched uranium out of the country. It can only do that with Iranian agreement, which will take time and require US concessions over sanctions. And whereas shipping moved freely through the Strait of Hormuz before the war, now it does not, and Iran has turned that into a bargaining chip.

Trapped again

The lesson is that superior force can knock things down and kill people, but does not necessarily give its holder the power to achieve objectives. The same lesson is unfolding in another theatre of operations: in the American campaign against drug traffickers, there have been over 60 attacks on small boats in the Caribbean and Pacific, killing more than 200 people. According to the latest studies, this has had no effect on the street price and availability of cocaine in US cities.

The problem in the Gulf is that Trump has taken his government into a hole from which it is hard to see a way out. We have encountered this before. It is a characteristic dilemma of a great power facing a resilient foe. Think not just Iran, but Ukraine. Think Vietnam.

In March 1968, at the height of the Vietnam War, as American opinion began turning decisively against it, Theodore Sorensen, President Kennedy’s former speechwriter, depicted the US predicament as being trapped in a six-sided box, which he described with three simple sentences: America’s military primacy could not produce victory, while its political primacy made withdrawal humiliating. It could not impose its will on South Vietnam or break the will of North Vietnam. Escalation risked Chinese or Soviet intervention, while serious negotiation meant accepting the possibility of a Communist South Vietnam.

It is not hard to apply the underlying analysis to the US against Iran. Some translation is needed: the war is unwinnable but withdrawal is humiliating; no ally is giving meaningful help and the enemy is too stubborn; all-out escalation is unthinkable, while good-faith negotiation means acknowledging that the war was wrong from the outset.

Hedging against US unreliability will be part of Europe’s and other US allies’ long-term policies for years to come

The US never managed to break out of that box in Vietnam and will probably be unable to do so in the Gulf. This failure – there is no other word for it – is draining the US capacity for strategic leadership. Allies are faced with reckless behaviour, frequent disregard and contempt, demands to back actions on which they were not consulted and which they oppose, inconsistent and misleading statements, and a war without strategy, legality or ethics.

It is hard to see how the US will regain the moral capital and leadership capacity it has lost this year. More bluster will not do it. Nor will resuming the war or coming to an agreement that makes major concessions to Iran. And it is currently impossible to see why Iran would make concessions to the US.

The United States remains the most powerful military actor in the world. But even the world’s strongest military cannot automatically translate force into political success. The danger is that future leaders continue to believe otherwise.

A strategically astute president who does not casually abuse and threaten allies may emerge in the future. But if the US electorate can do it twice, it can do it a third time — if not with Trump, due to age and the constitution, then with Vance, Rubio, Hegseth or someone else.

Accordingly, hedging against US unreliability will be part of Europe’s and other US allies’ long-term policies for years to come, maybe forever. As they become less dependent on the US, they will also be less compliant. In a few years, the US can restore much of its material power. Its non-material power will grow back only slowly, if at all.

Therein lies the most serious risk: that Trump, or a future leader, continues to believe against all the evidence that force equates to power, and uses it destructively, desperately and pointlessly.