The wars the UK has fought alongside the US – and when Britain has refused
TThe so-called ‘special relationship’ between the UK and the US has long gone hot and cold, but is now under critical strain as Donald Trump’s administration escalates the war in the Middle East.
The UK has not directly participated in the US-Israeli attack on Iran and, amid retaliatory strikes against countries in the region, the US president harshly criticized Sir Keir Starmer as “no Winston Churchill” after Washington refused to allow him to use UK bases to launch the first airstrikes on Tehran.
Churchill popularized the term “special relationship” in a 1946 speech, warning of the threat posed to the West by the Soviet Union following the end of World War II.
Since then, intelligence sharing, military cooperation, trade and cultural ties have linked the UK and US to varying degrees of dependence and trust, which have persisted despite changing global policies.
Here we examine which conflicts the two countries later fought side by side and which they did not.
Cold War (1947-1991)
The Cold War transformed the US-UK partnership into one of the tightest global alliances of the 20th century, with the special relationship providing the practical framework for how the West organized its defense and intelligence strategies.
Even as Britain’s global influence waned after 1945, Washington continued to rely on London as a reliable partner whose diplomatic weight, military support and intelligence capabilities helped establish the fulcrum of the West’s response to the Soviet Union.
The establishment of NATO in 1949 further strengthened ties by binding the two countries to a common military command structure and a long-term security commitment designed to fend off the communist threat.
Nuclear cooperation also deepened the relationship; The UK eventually adopted US systems such as Polaris and later Trident.
Korean War (1950-1953)
On June 25, 1950, North Korean forces invaded the South, triggering a major international crisis and the start of the Korean War.
Acting through the newly formed United Nations, the United States moved quickly to defend South Korea, beginning a grueling three-year conflict with heavy casualties, shifting front lines, and intense Cold War tensions.
Britain, a founding member of the UN, viewed the conflict as a critical test of the organisation’s ability to prevent aggression, and the US and UK relationship was at the center of UN-led efforts.
During the three-year war, Washington sent more than 300,000 troops; Britain contributed the second-largest contingent of more than 81,000 personnel, bolstering the UN’s naval force and taking part in some of the most challenging land operations of the conflict.
Together, the two countries formed the backbone of the coalition that repelled North Korean forces and shaped the initial military character of the Western alliance during the Cold War.
Vietnam War (1955-1975)
The conflict between North and South Vietnam, which spread into Laos and Cambodia, became the proxy war of the Cold War between the Soviet Union and the United States. Direct US military intervention began in 1965 and ended in 1973.
Despite intense pressure from US President Lyndon Johnson, Britain did not get involved. With the UK government facing economic constraints and a lack of public support, prime minister Harold Wilson decided to avoid costly, “unwinnable” conflict.
This led US officials to describe it as the “blood price” of the UK-US alliance.
However, Britain provided indirect support to America, including training US forces in jungle warfare, sharing intelligence, and providing military hardware. This diplomatic support came at a time when the US was providing significant financial support to the British economy.
Wilson explained his refusal to publicly condemn the Vietnam War: I tell a Labor colleague: “We can’t kick our creditors in the balls.”
First Gulf War (1990-1991)
The First Gulf War became a turning point for US-UK cooperation in the post-Cold War era, with troops from both countries fighting side by side for the first time since the Korean War.
The conflict began when Saddam Hussein sent Iraqi forces across the border to annex Kuwait, prompting a rapid international response under UN authority.
British prime minister Margaret Thatcher, in her final months in office, strongly supported US president George HW Bush’s insistence that aggression must be countered, and maintained this stance after John Major succeeded the Iron Lady.
Britain made the second largest military contribution to the US-led coalition, working closely with American commanders in air strikes, naval operations in the Gulf and ground offensives of Operation Desert Storm.
The war reaffirmed the special relationship by showing that London and Washington remained aligned on international security and the use of force.
Afghanistan War (2001-2021)
The Afghanistan War ushered the US and UK into a new era of intense military and political alignment, which began in October 2001 after Al Qaeda’s attacks on the World Trade Center and the Pentagon on 11 September and the Taliban’s refusal to hand over Osama Bin Laden.
President George W. Bush and prime minister Tony Blair forged a close partnership as the United States launched Operation Enduring Freedom, which began with airstrikes against the Taliban and Al Qaeda; Blair became Washington’s most vocal international supporter and committed British forces from the beginning.
Speaking on October 7 Blair said: “We know that sometimes we have to fight to keep the peace. Britain has learned this lesson many times in our history.
“If the case is justified, we will do it, but this case is justified… We waited for those responsible to be handed over by those who protect them. The offer was rejected, we have no other option now, we will take action. And our determination to act is complete. We will not give up, we will not rest until we fully achieve our goals.”
The UK provided the largest military deployment outside the US, working with American forces in combat operations, counterinsurgency efforts and later NATO-led stabilization missions.
The war became increasingly controversial, as civilian casualties, allegations of mistreatment of detainees, and growing doubts about the long-term strategy fueled public and political criticism on both sides of the Atlantic.
The Taliban launched a major offensive in the summer of 2021 and successfully reestablished control over Afghanistan as U.S. forces withdrew under the terms of the 2020 agreement.
Second Gulf War (2003-2011)
After accusing the Hussein regime of possessing weapons of mass destruction and defying UN disarmament resolutions, the US-led coalition once again drew the US and Britain into a tightly coordinated military and political partnership.
The conflict began in March 2003, when US-led forces invaded Iraq and saw George W. Bush and Blair again leading the international offensive.
Blair committed British forces to the initial invasion and the long occupation that followed.
The UK provided the second largest military contingent, worked closely with US commanders in southern Iraq, and aligned itself with America’s strategic objectives despite domestic backlash and international controversy.
Speaking later about the state of the special relationship, Bush said: “Some of our allies hesitated, but Tony never hesitated.”
But the UK’s decision to support the war was long controversial and weighed heavily on Blair’s legacy. The damning Chilcot inquiry in 2016 found the invasion was unnecessary and support was gained through misrepresentation of evidence.
Libya (2011)
The intervention in Libya in 2011 brought the US and the UK into a different arena of military and diplomatic coordination, this time under President Barack Obama and Prime Minister David Cameron.
The conflict began when the uprising against Libyan leader Muammar Gaddafi was met with violent repression and the UN authorized military action to protect civilians.
Britain and France pressed hardest for intervention, and the United States provided early assistance in the form of air power, intelligence and cruise missile strikes before shifting to a supporting role.
The UK worked closely with American forces during the initial assault on Libyan air defenses and throughout NATO’s subsequent campaign, deploying fighter jets, warships and surveillance aircraft.
The NATO-led campaign ended with the collapse of Gaddafi’s regime in late 2011, after sustained airstrikes and rebel advances killed Gaddafi and forced his regime from power.
