THOUGH considered an abject failure by many, the enormous British anti-war movement against the 2003 Iraq War has had a number of long-lasting impacts on British politics and society.

One unfortunate effect is, nearly 20 years later, the movement’s inability to stop the invasion continues to breed defeatism when it comes to the general public influencing British foreign policy.

For example, discussing the large-scale British protests against the recent Israeli bombardment of Gaza, one Middle East scholar quipped on Twitter, “If history has taught me anything, when people in Britain march against immoral actions in the Middle East, their government will almost certainly ignore them.”

This pessimistic take is even shared by anti-war figureheads like Tariq Ali, who spoke at the rally in Hyde Park in London at the end of the biggest march in British history on February 15 2003. “It was a huge show of anger, but that’s about it. It left no lasting legacy,” Ali commented on the tenth anniversary of the demonstration.

So should we be disheartened? History suggests there is cause for optimism.

Take the Vietnam War and the US anti-war movement that opposed it. Elected in 1968, “President Richard Nixon claimed in public to be completely unmoved by anti-war protests,” academic Simon Hall notes in his book Rethinking the American Anti-War Movement.

The reality was rather different. Both Nixon and president Lyndon Johnson before him “took an active interest in the movement’s doings,” Tom Wells explains in his 1994 book The War Within: America’s Battle Over Vietnam. Indeed, Nixon “received multiple reports per day on some demonstrations.”

Admiral Thomas Moorer, the chair of the joint chiefs of staff during Nixon’s presidency, told Wells, “The reaction of the noisy radical groups was considered all the time,” with the wider movement having “a major impact… both in the executive and legislative branches of government.”

With the movement playing “a major role in constraining, de-escalating and ending the war,” it “was perhaps the most successful anti-war movement in history,” Wells concludes.

In short, the US anti-war movement of the late 1960s and early 1970s was able to inhibit the war policy of the most powerful nation — and biggest war machine — the world had ever seen.

Impressive stuff. But British anti-war activists don’t need to look across the Atlantic for inspiration.

Having trawled the National Archives on post-war British foreign policy, in his 2004 book Unpeople: Britain’s Secret Human Rights Abuses, Mark Curtis notes “the public is feared” by Britain’s government. “A perennial truth which emerges from the declassified files is the public’s ability to mount protests and demonstrations that divert the government from its course.”

In the late 1950s British forces were involved in crushing an uprising against the British-backed sultan of Oman. Curtis notes the senior British official in the region — the “political resident” in Bahrain — had recommended three villages be bombed unless they surrendered the ringleaders of the revolt.

However, the government initially decided not to bomb because, they argued, “world opinion at that time was very flammable” (the bombing did happen in the end). The commander’s report at the end of the intervention noted “great pains were taken throughout the command to keep all operational actions of the press.”

By the 1960s, the ongoing US aggression in Vietnam had generated considerable anti-war activity in Britain, including some high-profile demonstrations. By 1965 the British ambassador in Saigon noted “mischievous publicity” about the war from the anti-war movement, which “is having an effect on the policy of Her Majesty’s government.”

Curtis disagrees, explaining Britain backed the US war in Vietnam “at virtually every stage of military escalation.” What was happening? Noting there was an “organised campaign” against the war, in 1965 Foreign Office official James Cable reported: “All this has not yet affected our basic support for American policy in Vietnam, but it has generated a certain preference for discretion in the outward manifestation of this support.”

So the government continued to follow their preferred policy, just out of the public eye — not much to shout about, it could be argued. However, it’s important to remember the bigger picture. Despite significant pressure from president Johnson, prime minister Harold Wilson refused to send regular British troops to Vietnam (a small number of British special forces did fight in Vietnam).

According to History Extra, the official website for BBC History Magazine, one of the main reasons Wilson gave was it “would be extremely unpopular with his party and the wider public.”

The British establishment’s fear of the public is not confined to the distant past. Starting in late 2001, the government’s huge propaganda campaign to persuade the public to back the Iraq War underscores just how seriously it was concerned about public opinion.

According to the Guardian, days before the onslaught started the Spanish UN ambassador noted in a memo to Spain’s foreign minister that Britain had become “exclusively obsessed” with domestic public opinion.

Reporting on leaked documents, in November 2003 the Guardian also revealed “a [MoD-organised] media offensive aimed to convert British public to supporting the outcome of the Iraq War.” According to the papers “the MoD’s [Ministry of Defence] main target is UK public and media while [the main target] of the Basra headquarters for British troops is the Iraqi people.”

Though it is rarely framed as such, the momentous vote in the House of Commons against British military action in Syria in August 2013 — the first time a British prime minister had lost a vote on war since 1782 – can be considered a delayed impact of the anti-Iraq War movement.

“The spectre of the 2003 Iraq war hung over the Commons,” the Guardian reported at the time, with Labour leader Ed Miliband apparently telling Prime Minister David Cameron, “You have to realise that after Iraq nobody trusts any of us.”

This historic defeat sent shock waves through the British political and military establishment.

Speaking at the international affairs think tank Chatham House in September 2015, Sir Nick Houghton, Britain’s chief of defence staff, argued, “We are experiencing ever greater constraints on our freedom to use force” with “the more worrying constraints on the use of force lay[ing] in the areas of societal support, parliamentary consent and ever greater legal challenge.”

The year before, former Labour Party defence secretary Lord Browne conceded “the British public have made it clear that there is very little support for new expeditionary wars of choice, even where there is a national security dimension.”

Of course, the British military were not simply passive bystanders during this shift in public opinion. In September 2013 the Guardian carried an extraordinary front-page story which further highlighted the power of Britain’s anti-war movement and the general public.

Titled “MoD study sets out how to sell wars to the public,” the report summarised a November 2012 MoD document, obtained under the Freedom of Information Act: “The armed forces should seek to make British involvement in future wars more palatable to the public by reducing the public profile of repatriation ceremonies for casualties.

“Other suggestions made by the MoD think tank in a discussion paper examining how to assuage ‘casualty averse’ public opinion include the greater use of mercenaries and unmanned vehicles, as well as the SAS and other special forces, because it says losses sustained by the elite soldiers do not have the same impact on the public and press.

“The public have become better informed,” the MoD paper warned, recommending the armed forces run “a clear and constant information campaign in order to influence the major areas of the press and public opinion.”

Back to the anti-Vietnam War movement. Wells comes to a worrying conclusion: despite its huge impact on the US government’s actions in Vietnam, at the time “few activists fully appreciated the considerable political power they possessed,” which “spawned defections from the movement… bred lethargy, stagnation and despair in the movement’s ranks, impeding the organisation of protests and the maintenance of anti-war groups.”

All of which will be very familiar to peace activists working today.

Of course, we shouldn’t exaggerate the power of grassroots activism. But a good knowledge of the history of British foreign policy, and how this interacts with social movements and public opinion, can provide a valuable grounding for maximising our influence on future government foreign policy.

Ian Sinclair is the author of The March That Shook Blair: An Oral History of 15 February 2003, published by Peace News Press. Follow him on Twitter @IanJSinclair.