In Britain, the alarm about the NATO decision was sounded by E. P. Thompson (1979), fittingly in the New Statesman and elsewhere, 21 years after J. B. Priestley's essay that launched CND. He expressed the core argument that would be made across Western Europe in the next four years: “why, since there is already terror enough, ten times over, ballistically poised at both end of Power's great divide, do we need this intermediate additive of terror at all? Ah, it is a safeguard to prevent the ultimate horror of a Soviet/US nuclear war! It is to ‘localize’ nuclear war: that is, to keep nuclear war local to us, and to West and East Europe, and away from America” (emphases in original). Attacking the secrecy and lack of democratic accountability, as well as a reported British decision a month earlier to replace Polaris by Trident, Thompson returned to the case for active neutrality that the New Left had advanced 20 years earlier.

He followed this clarion call with private overtures to prominent left-wing Labour MPs Tony Benn and Eric Heffer. However, it was after Ken Coates of the Bertrand Russell Peace Foundation rang him that the first steps were taken towards a pan-European campaign against the cruise and Pershing missiles. Coates had worked with East European and Soviet dissidents over the previous decade and had been calling for a new European initiative: NATO's decision and Thompson's outcry gave him the target that he had been lacking. With input from Coates, Mary Kaldor and Dan Smith, Thompson then drafted an Appeal for European Nuclear Disarmament, which was widely discussed and circulated for signatures in Britain and elsewhere before being publicly launched in London, Oslo, Paris, Berlin and Lisbon on 28 April 1980 (Coates 1987: 11–14; Burke 2004: 39–52).

The Appeal (European Nuclear Disarmament 1980) provided a political framework that would inspire much of the campaigning across the continent throughout the 1980s, and endorsing it was the basis for being involved in the END process. Unlike CND's constitution, which framed the nuclear problem as one that should be solved first by national action, it developed a European approach and addressed the political underpinning of the nuclear arms race, the Cold War.