What happens if the USA strikes Iran?

Anika Samant is a first-year Bsc Politics and International Relations student. She is passionate about diplomatic relations and global affairs, with a particular interest in the

Russia-Ukraine conflict (anika.samant.25@ucl.ac.uk).

Introduction

Relations between Washington and Tehran have long been defined by shared aggression, hostility, proxy wars, and contention over Iran's nuclear and ballistic missiles programmes. A direct military confrontation would mark a significant escalation in tensions, with consequences extending far beyond just the two states involved. This article argues that the four most likely results of an American strike on Iran are: the outbreak of war, a gradual transition to democracy, the survival of the regime albeit with moderate politics, or the collapse of the regime.

Outcome 1: The Possibility of War

The most likely immediate possible outcome of the USA striking Iran is warfare. If Iran retaliates, this could lead to an escalation of conflict involving more and more countries.

Iran possesses ballistic missiles and drones which are hidden underground, in caves, or remote mountainsides. It could launch a swarm attack, deploying vast numbers of highly explosive drones and fast torpedo boats at single or multiple targets over a long period of time [1], preventing the US navy's formidable close-in defences from eliminating them. It could target US bases and facilities positioned along the Arabian side of the Gulf, or in Bahrain or Qatar. Most damagingly, it could target Jordan or Israel. Furthermore, Iran could also launch missiles targeted at a USA warship with the aim of sinking it. If this occurs, this would be a large humiliation for the country [2]. Although such an outcome may seem unlikely, history shows that US warships have been severely damaged before. In 2000, the USS Cole was crippled by an Al‑Qaeda suicide attack in Aden harbour, killing 17 sailors, and in 1987 the USS Stark was struck by two Iraqi Exocet missiles, resulting in the deaths of 37 sailors [2]. Iran could also launch an economic attack on the USA by shutting the Strait of Hormuz, a critical point of oil transfer: around 20% of the world's LNG exports and oil products pass through this strait each year [2]. If this happens, oil prices in the USA would jump dramatically, since military action could shake investors’ confidence in a region that relies heavily on foreign direct investment [6]. US officials also expect sustained back-and-forth reprisals over weeks, increasing the likelihood of a wider regional war drawing in neighbouring states [5]. Iran has warned that US military bases across the Middle East would be considered legitimate targets, further heightening the risk of escalation and regional destabilisation [2].

Outcome 2: Gradual Transition to Democracy

Secondly, a conflict between Iran and the USA could theoretically create conditions for a gradual transition to democracy in Iran. US air and naval forces could conduct limited precision strikes targeting military bases of Iran's IRGC and its Basij unit, which would seriously weaken the regime's stability. Taking Iraq and Libya as case studies, the BBC has argued that military intervention could further destabilise the region, causing immense bloodshed, chaos, and a humanitarian catastrophe rather than stable democratic outcomes [2]. Moreover, the USA could launch a strategic campaign aimed at achieving fundamental changes in the current regime, such as accepting strict limitations on its ballistic missiles and its proxies’ activities, which could even trigger political change. However, the USA would need to present a credible threat to the current regime's survival, which would require a sustained, well-coordinated military campaign supported by regional allies, which would force the regime to choose between survival or a conflict [6]. This scenario could fracture the state internally, risking chaos and civil war. As Iranian officials themselves warn, a war would leave the whole region “in a mess,” underlining the unpredictability of any post-regime outcome [2].

Outcome 3: Survival of the Regime

A third potential outcome is the survival of the regime, but in a moderated and constrained form. Under this scenario, the leadership would remain in power but face significant external pressure from the USA to recalibrate or moderate its social, cultural, economic, and possibly foreign policies. This could potentially involve the reduction or withdrawal of support for violent militias across the Middle East. This would limit the expansion of Iran's domestic nuclear and ballistic missile programmes, and ease the suppression of domestic protests, dozens of which the leadership faces each year. These adjustments would likely be caused by economic strain, diplomatic isolation, and the desire to secure renewed international engagement. However, these outcomes remain unlikely [1]. Historically, the regime has prioritised ideological consistency and strategic deterrence over reform, thus meaningful concessions could be perceived as a sign of weakness internally, which could threaten its long-term grip on power. Furthermore, established hardline factions within the political and security system may resist considerable change, fearing that restraint could embolden opposition parties and gradually erode the ideological foundations of the regime, as well as its authority [1].

Outcome 4: Collapse of the Regime

A fourth and final outcome of a strike on Iran from the USA is the collapse of the regime. A limited coercive strike could force Iran back to negotiations from a weaker position. This would have a limited effect on the regime's calculus, and would not guarantee a manageable military confrontation, as Iran has stated that it would carry out retaliatory measures [5]. The collapse of the regime would lead to the replacement of US military rule, during which Iran would be ruled by a strong military government composed mainly of IRGC figures. However, this could also result in a civil war, where ethnic tensions could spillover into Kurds, Baluchis, and other minorities. In the Kurdistan Region of Iraq (KRI), separatist activism has long been prevalent.

Groups such as Komala and PJAK have already been accused by Iran of instigating terrorist attacks [3]. In southeastern Iran, in the Baluchistan province, armed clashes between the state and militant groups have continued for years and years [3]. The collapse of the regime could exacerbate tensions and plunge Iran into prolonged internal conflict, resulting in a humanitarian and refugee crisis [1].

Advocates of military action, such as the Atlantic Council, a nonpartisan think tank, argue that Iran is currently at one of its weakest points in decades [3]. They suggest that decisive action could reshape regional relationships and weaken Tehran's proxy networks across the Middle East. However, history demonstrates that regime collapse can facilitate power vacuums, which can invite factional struggles, empower hardline military figures such as elements of the IRGC, or encourage foreign interference from rival powers which seek influence. Therefore, Iran could experience prolonged instability, economic collapse, and intensified repression before any meaningful political reform [4].

Conclusion

To summarize, a US strike on Iran would carry profound and unpredictable consequences which could extend far beyond a short-term military exchange. While immediate outcomes would most likely be escalation and regional warfare, other scenarios, such as a constrained and moderated regime, democratic transition, or total collapse, remain possible. Ultimately, any decision to use force against Iran would simply not be a tactical calculation, but a strategic gamble with long-term implications for regional stability and the international order.

Works Cited

[1] Doucet, L. and Culley, J. (2026). Iran ready to consider compromises to reach nuclear deal, minister tells BBC in Tehran. BBC News. [online] 15 Feb. Available at: https://www.bbc.co.uk/news/articles/clyz4y3zwz5o.

[2] Gardner, F. (2026). What could happen if the US strikes Iran? Here are seven scenarios. [online] BBC News. Available at: http://bbc.co.uk/news/articles/ce3kenge1k9o [Accessed 23 Feb. 2026].

[3] Jafari, S. (2026). Why a military strike on Iran could spark a civil war. [online] New Statesman. Available at: https://www.newstatesman.com/world/2026/01/why-a-military-strike-on-iran-could-spark-a-civil-war.

[4] Michael Rozenblatt (2026). Six reasons why Trump should choose the military option in Iran. [online] Atlantic Council. Available at: https://www.atlanticcouncil.org/blogs/menasource/six-reasons-why-trump-should-choose-the-military-option-in-iran/.

[5] The Jerusalem Post | JPost.com. (2026). US military preparing for weeks-long Iran operation | The Jerusalem Post. [online] Available at: https://www.jpost.com/middle-east/article-886588 [Accessed 23 Feb. 2026].

[6] Youssef, N.A. (2026). The Atlantic. [online] The Atlantic. Available at: https://www.theatlantic.com/national-security/2026/02/iran-trump-war-us-israel-netanyahu/685970/ [Accessed 23 Feb. 2026].