Al-Qaida's attacks on New York and Washington, DC on 11 September 2001 (9/11) shocked peace campaigners as much as anyone. As President George W. Bush declared a “global war on terror”, which Blair supported, it was soon obvious that activists would continue to be concerned as much with wars as with weapons, and that the wars could be larger and even more consequential than the interventions in former Yugoslavia. In the first years of the new century, while the campaign against nuclear weapons remained politically marginal, an enormous antiwar movement rapidly developed.

In Britain, this movement drew in all shades of antinuclear activists in the build-up to the great demonstration against the Iraq War on 15 February 2003. However, when it subsided, it left effects that persisted during the following two decades. First, it created a lasting alliance of CND with the main antiwar organization, the Stop the War Coalition (StWC). Second, it also consolidated, after considerable turbulence in 2003–4, CND's own internal coalition of Christians and pacifists with the far left that had been reconfigured in the 1990s.

This chapter therefore begins by discussing the roles of antinuclear campaigners in the post-9/11 movement, before turning to the continuing campaign against nuclear weapons by both CND and direct action groups. Further wars often galvanized campaigners more than nuclear developments, but political turbulence within Britain created significant openings to challenge the Trident nuclear system, which remained the main focus of antinuclear campaigning throughout the first quarter of the century.

CND and the new antiwar movement

CND held its annual conference five days after 9/11. The organization was already fielding thousands of calls from people looking for it to take a lead, as Britain's main peace campaign, in opposing Bush's threatened intervention in Afghanistan. Under a newly elected chair, Carol Naughton, and vice-chair, Kate Hudson, it immediately called a “No retaliation, no war” vigil outside Downing Street. Using email, which most activists had by 2001, this mobilized thousands (Sinclair 2011: 105–6).

Others were also organizing. The Socialist Workers Party (SWP) called a public meeting to “stop the war before it starts” on 21 September 2001, which attracted 2,000 people representing a range of left opinion. With their representative Lindsey German in the chair, speakers included Jeremy Corbyn MP and the environmentalist George Monbiot as well as far-left spokespeople.