Wilson feared Communists on CND march

There were concerns about the CND march after anti-Vietnam riots

The secret services warned former Prime Minister Harold Wilson that Communist agitators were planning to infiltrate the CND Aldermaston march following riots in 1968, according to official papers released under the 30-year rule.

Anti-Vietnam war protests which led to rioting in Grosvenor Square in March 1968 led to deep fears within the establishment about the annual Campaign for Nuclear Disarmament march on the Aldermaston weapons plant.

Although the Easter march had no history of violence, there was a widespread fear it would be the next catalyst for "revolutionary" violence, according to papers made public for the first time at the Public Record Office.

Up to 800 police were to be drafted in for the event as MI5 had recognise violent elements would be attracted to the event, according to a memo from then Home Secretary James Callaghan to Mr Wilson.

The permanent secretary at the Ministry of Technology Sir Richard Clarke wrote to the Head of the Civil Service Sir Laurence Helsby to assure him in the "current climate of violent protest", particular attention would be paid to security.

Harold Wilson: Suggested helicopters for troop movement

Thames Valley Police had warned "the more militant representatives of the Vietnam Solidarity Campaign and other groups" might take over the running from the more moderate CND elements.

"Their view is that we must reckon with the possibility of a mass attack upon the perimeter fence of the factory," Sir Richard stated.

"Violent penetration of the various concentric physical defences would, if successful in the very difficult task of scaling or cutting three separate permanent barriers and in overcoming the active defence of the police, ultimately reach the magazine and Polaris warhead assembly areas.

"If, in the extreme case, magazines were set on fire, there would certainly be explosions. Only lengthy hard work by experts, however, could afford access to the bunkers containing fissile material."

Home Secretary James Callaghan was drafted in to reassure the prime minister events were under control.

James Callaghan: Tried to reassure prime minister

In a memorandum to Mr Wilson, Mr Callaghan said that, while MI5 believed the event could attract violent elements, the number of police available would be more than 800 - "much larger than on any previous Aldermaston march".

He wrote: "Present indications from the Security Service (MI5) are that there will be contingents from the Communist Party, together with representatives from West Germany and other Nato countries as well as Japan and New Zealand.

"It is to be expected that individual members of some of the Trotskyist and anarchist groups associated with the disorder last month in Grosvenor Square will also participate."

He added MI5 had no reason to believe that violent action was planned, however Mr Wilson was still not satisfied with the arrangements.

The prime minister replied to Mr Callaghan, urging him to arrange for some military helicopters to be earmarked for the rapid transport of troops, adding "there may be other ways - eg. guard dogs - in which the Forces could help".

In the event, their fears were unfounded and the year saw no repeat of the events of Grosvenor Square, at Aldermaston or anywhere else.

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Leviathan - UK Confidential
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