US aircraft carrier

Forever wars

Last updated 25 May 2021

Since the attacks on the World Trade Centre and the Pentagon carried out by Al Qaeda on September 11 2001, the US has been continuously at war in numerous countries around the world. Initially dubbed a “Global War on Terror”, these wars have come to be seen as “forever wars” – unending conflicts against a shifting series of enemies, mostly non-state armed groups with little or no connection to the original Al Qaeda group, in a futile pursuit of security through bombing. These wars, most prominently the invasion of Afghanistan in 2001 and the illegal invasion of Iraq in 2003 – in both of which the UK was a key ally – have caused hundreds of thousands of civilian and military deaths, displaced millions of people, and devastated societies and economies across the Middle East and beyond, while costing the US trillions of dollars.

The ‘Global War on Terror’

Following the terrorist attacks by Al Qaeda on the World Trade Center and the Pentagon on 11th September 2001, killing nearly 3,000 people, US President George W. Bush declared a ‘Global War on Terror’. Within a week, the US Congress passed, almost unanimously, an Authorization for the Use of Military Force (AUMF), enabling military retaliation by the US. While theoretically directed against Al Qaeda and allied forces, the AUMF was interpreted by successive administrations as allowing military force against any country or group considered by the US to be a threat or acting contrary to its interests. The designation by President Bush of Iran, Iraq, and North Korea as an “Axis of Evil” in January 2002 set the stage for aggressive military action in the years to come.

The US-led invasions of Afghanistan and Iraq in 2001 and 2003 respectively – both carried out alongside the UK – were the biggest wars that followed the War on Terror declaration, but far from the only ones. (See map below). The US and UK launched a bombing campaign to overthrow the Taliban regime in Afghanistan in October 2001, with the stated justification that the Taliban were harbouring Osama bin Laden and Al Qaeda, responsible for the 9/11 bombings. The 2003 invasion of Iraq by the US, UK, and Australia, an act of aggression that was clearly illegal under international law, was based on the false claim that Iraq possessed weapons of mass destruction, and (by the US) the equally false claim that Iraqi dictator Saddam Hussein had collaborated with Al Qaeda in the 9/11 attacks. US forces have remained in both countries ever since, apart from a 3-year gap in Iraq from 2011-14.

President Joe Biden has pledged to end the “Forever Wars”, and has announced a complete US military withdrawal from Afghanistan by September 11 2021. But there is no sign of an end to the US’s other military engagements.

World map displaying location and nature of US military operations, with various symbols

US Counterterrorism operations 2018-20

This map, produced by the Brown University Costs of War project, shows the locations and types of US military activities labelled as "counterterrorism" during 2018-20.

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Worldwide wars

While the “Global War on Terror” label was abandoned by the Obama administration, the wars it spawned were not, and have continued to spread around the globe. Since President Obama came to power in 2009, the US has generally sought to reduce the number of troops directly involved in combat, in the face of deepening unpopularity of the wars among the US public, as a result of high levels of troop casualties. Instead, the US has increasingly relied on air and drone strikes and special forces operations, often in support of allied local forces, be that governments or non-state armed groups.

Between 2018 and 2020 (see map and linked paper), the US carried out air and drone strikes in seven countries: Afghanistan, Iraq, Libya, Pakistan, Somalia, Syria, and Yemen. US forces were involved in combat operations (either directly or acting in command of local surrogates) in 12: Afghanistan, Cameroon, Iraq, Kenya, Libya, Mali, Niger, Nigeria, Somalia, Syria, Tunisia, and Yemen. Counting countries where the US has engaged in military exercises with government forces, and/or provided them with training and equipment under a counterterrorism label, the US was involved in military operations in 85 countries worldwide during this period.

Drone wars

Drone strikes in particular have been used as a means of targeted killing of suspected ‘terrorists’ in numerous countries, including Afghanistan, Pakistan, Somalia, and Yemen. Some strikes have been carried out by the US military, others by the CIA, with even less oversight than for regular military operations. At times, the US has maintained a ‘kill list’ of individuals it considers legitimate targets for drone killings – essentially, extrajudicial executions, without any semblance of due process. This list has sometimes included US citizens. Rules of targeting have varied, but at times the US has adopted a policy of ‘signature strikes’ based on an individuals patterns of behaviour – who they meet, where they go, etc. In areas where possession of firearms such as AK-47s by men is routine, this has sometimes meant that any male of fighting age could potentially be a target. The precise number of civilians killed in these strikes is not known, but the independent Bureau for Investigative Journalism estimates a figure of 910-2,200 since they started counting in 2010, including 283-454 children. This is out of a total of 8,858 – 16,901 people killed in such strikes. However, in many cases, the identity of people killed is unknown.


Key statistics

770,000 - 801,000

People killed in major wars involving the US 2001-Oct. 2019

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Budgetary cost of US wars since 9/11, up to Sep. 2020

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The human cost

The wars waged by the US since 9/11 – and the ongoing conflicts that have broken out as a result, and which may continue long after US forces have left – have caused untold death and suffering around the Middle East, South Asia, and parts of Africa. The Brown University Costs of War project estimates that up to 800,000 people had been directly killed in the major war zones where the US has been involved since 2001, including well over 300,000 civilians. These include Afghanistan, Pakistan, Iraq, Syria (in the part of the conflict between the US and ISIS), and Yemen. This does not include those who have died from disease and hunger that has come in the wake of these wars. The biggest civilian toll was in Iraq, where 184-207,000 civilians were killed, followed by Afghanistan, where 43,000 were killed.

In addition, 37 million people have been forced to flee their homes as a result of the post-9/11 wars involving the US in Afghanistan, Iraq, Libya, Pakistan, Somalia, Syria, and Yemen, inflicting further trauma and suffering.

The financial costs

Beside these horrific human realities, to speak of economic costs may seem banal – but the vast sums of money spent on these wars represent human and material resources that could have been used for other purposes, such as health, education, and relief of poverty in the US and worldwide. The figures for the US are staggering, estimated at $6.4 trillion up to Fiscal Year 2020 (ending Sep. 2020), including the direct cost of military operations, additional arms spending resulting from the wars, the current and future costs of healthcare and other spending to support war veterans, and future interest on the national debt incurred as a result of the government borrowing that financed the wars.

The economic costs to the countries where the wars were waged, in terms of destroyed infrastructure, trade, and livelihoods, is almost impossible to measure accurately, but is certainly immense.

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