Three military lessons from the Iran war

The announcement of a two-week ceasefire between the US and Iran was a welcome development, although many of its details, as well as the actual facts on the ground in the theatre of operations, remain very much unclear and indeed disputed. So far, this has been a remote fight, with little frontline reporting of any credibility, wrapped in fake AI imagery, and with coverage now deprived even of much of the commercial satellite imagery that had become so pervasive and important during the last few years, certainly since 2022. 

The fog of war has been thicker in this conflict, more than in almost any other recent one. Therefore, any discussion on “lessons” to be drawn from it – so far – must necessarily be taken merely as tentative propositions based on preliminary, general analysis, and can only be put forward with restrained confidence. Nonetheless, this is an important exercise to undertake as early as possible, given how quickly military affairs are evolving. 

Even from the observable evidence, the Iran campaign has been exceptionally significant from a military and strategic standpoint and may well be seen by future historians as a watershed in the long history of war itself. Three key, distinct potential lessons arguably stand out at this point – again, not as much as definitely proven conclusions, but more as hypotheses that may invite further reflection, and that are presented here in a deliberately provocative manner for that same reason:

The first lesson is that for major powers war of aggression is useless in our time and perhaps in the longer run as well. In 21st century state-on-state conflict, even the strongest nations find it at first difficult, and eventually impossible, to overthrow their enemies by force of arms. Russia and America have now proven this in Ukraine and Iran, but evidence towards this proposition has been accumulating for over a century. 

In both World Wars the aggressors lost, and in between them the Soviet invasion of Poland failed, while Japan’s China campaign from 1931 also didn’t work out in the end. Korea in the 1950s was at best a draw, as was the Iran-Iraq war in the 1980s. Attacks and interventions against Israel and Vietnam also met with eventual defeat, as did Argentina’s attempt at the Falklands and Saddam’s invasion of Kuwait which triggered the First Gulf War. America’s invasion of Iraq in 2003 is, somewhat like Japan’s of China, considered an initial military victory but an overall strategic failure. As for Afghanistan – not strictly an appropriate example given its quasi-state outlook – it defeated aggression against itself by both the Soviets and Americans. The Russo-Japanese war of 1904-5 and the NATO bombing of Serbia might be adduced as some of the only examples of the contrary, but one is from over a century ago and the other stretches the bounds of our definition.

Aside from the weight of the historical record, there are the practical reasons why war just doesn’t work well as a tool of policy for major states – not anymore, at least. The main reason is that explored in these very pages some two years ago, when I explained that “insufficient destruction is why no one wins wars anymore”. 

In short, the point is that unless an attacker forces very quick and complete collapse of the enemy, then the conflict becomes one of attrition. To win in this kind of situation, the attacker must either gain decisive superiority at the front and thus break it; and/or it must pulverise the rest of the country and its support infrastructure in the rear. Today, breaking the front is exceedingly difficult, as shown in Ukraine: In our networked world, any country attacked by a major power is almost guaranteed effective support by that power’s major adversaries, which will help it hold the frontline steady.

So the only other way to victory is simply to physically destroy the other side’s key infrastructure and capacity to fight. In turn, this requires a great deal of explosive ordnance and the ability to deliver it on target in short order – to prevent repairs and rebuilding. The sheer capacity to “blow up things” in the rear, which is needed on top of the resources needed at the front, is where modern campaigns fall short. America’s failure to pound its way to victory from the air in Iran is only the latest example of this.

Very briefly, the second “lesson” from the Iran war is that long-range warfare is the future. The continuous development of drone and missile technology is increasing the range and lethality and is decreasing the costs of these weapons. This is now coupled with ever more accessible surveillance and targeting capabilities, including from space. The net result is now the proliferation of sophisticated, complex and highly capable weapons systems for long-range strike. 

Until a decade ago this kind of sustained long-range strike campaign was only within the means of the US military through long-range aviation and Tomahawk Land Attack Cruise Missiles. Russia, China and a few others to a lesser extent also had planes and missiles, but fewer of them, less capable, and certainly would have lacked the targeting ability, let alone the ability to penetrate Western air defences repeatedly, or even at scale.

Long-range warfare is here to stay, and we are not ready for it despite the experience of Ukraine. From a strategic and doctrinal point of view the distinctive implication of this form of attack that is now morphing into a form of warfare, is that such campaigns can be conducted at arm’s length and the attacked party – the defender – may have no means to hit back effectively, in kind, in order to make the attacker desist. The requirements of this kind of warfare – conducted at scale – are vast, and come on top of already-stretched defence budgets. This raises profound strategic questions for military “laggards” like the UK.

The third lesson is that sea power is in decline. It has long been an axiom in Western military thought that sea power is the key to global power and security. The US Navy, not the “rules based international order”, has been more responsible for the preservation of freedom in the world after 1945 than arguably any other single thing. The greatest European empires, most obviously Britain’s, were build on naval strength, and naval theorists have traditionally been convinced that control of the oceans and chokepoints – control of seaborne trade – are the secret to defeating great land powers, as happened with the blockade of Germany in the First World War, and with the instrumental Atlantic and Pacific campaigns in the Second. 

The Iran war, however, has confirmed what the Ukraine war had demonstrated in the Black Sea maritime theatre: That warships are now extremely vulnerable to shore-based attack capabilities – the long-range strike weapons discussed above, but also maritime drones – and that they cannot be operated “safely” anywhere near the shoreline. Indeed, during the recent Iran operations, the US Navy felt it had to pull back its aircraft carrier, the USS Abraham Lincoln, to such a distance in the Arabian Sea (south of Oman) that US planes flying off it on bombing missions into Iran had to be refuelled in mid-air in order to reach their target. 

The entire saga over the question of how to reopen the Hormuz Strait – following on from the struggles against the Houthis – is likely to be remembered by future naval historians as a turning point in the field. Whether there was enough practical naval capability “technically” available to deal with that situation, across the entire fleet, is neither here nor there. The point is that the ostensible cost of such an operation, the risks involved, were judged to be politically unpalatable – so the “instrument” could not be used.

The ranges involved in this maritime theatre of operations, as those pertaining to the Black Sea, at the very least raise profound questions as to the continued relevance of key types of naval assets – certainly in terms of large surface combatants – in most maritime environments of potential future conflict, not just in and around Europe, but also further afield. Expensive warships are indeed useful as floating platforms for long-range land-attack and air-defence missiles, but if they are pushed back so far that those missiles might as well be based on land somewhere, why have them in the first place? 

This does not apply to the same degree to submarine warfare – yet. But sensor technology, including quantum sensing, as well as underwater drone technology, are advancing rapidly and it is an open question as to how safe will submarine operations remain and for how long in the future, particularly in shallower waters. All this is even before the impact of space power on naval warfare is considered, including in terms of future orbital strike capabilities that may come to hold at risk highly valuable naval assets anywhere on the high seas.

The three propositions as to the lessons of the Iran war discussed here – from the ineffectiveness of war as an instrument of policy in the contemporary world, to long-range warfare and the decline of sea power – are just some of the more prominent conclusions about the changing character of war in our time that this conflict is confirming. 

There are others, too, such as the clear prospect for a renaissance of fortification – both military and urban, in response to crime and threats of civil war. Or the fact that the age of alliance-based “deterrence” in the classical sense is over – as both Putin’s and Trump’s grand (and similar) wars indicate – not least because calculations of the military balance now escape our traditional models and frameworks.

Of course, the real tragedy in all this is that however well we understand such lessons – and our governments most assuredly do not understand them – there is hardly anything that can be done about them. For it is certain that the next war, if or when it comes, will find us woefully unprepared, as always. The trick is to have enough national resources and capacities in reserve in order to recover from the inevitable initial setbacks, reform under fire, and turn the tide against our adversaries. They are not as strong as they seem, either.