President George Bush, hijacked by hardliners in his administration, is setting the world on a course towards nuclear disaster, a founder of the nuclear deterrence policy said.
The 1995 Nobel peace laureate, Professor Sir Joseph Rotblat, accused the US of developing a policy which regarded nuclear weapons as bad if in the possession of some states or groups but good if they were kept by the US for the sake of world security.
The fact that it had signed the non-proliferation treaty and was legally bound to the elimination of nuclear weapons was ignored, he told the Guardian-sponsored non-proliferation conference, jointly hosted by the Royal United Services Institute for Defense Studies and Physicians for Social Responsibility.
"Nuclear arsenals will have to be retained indefinitely, not just as a weapon of last resort, or as a deterrent against a nuclear attack, but as an ordinary tool in the military armory, to be used in the resolution of conflicts, and even in pre-emptive strikes, should political contingencies demand it.
"This is in essence the current US nuclear policy, and I see it as a very dangerous policy."
Sir Joseph said that Mr Bush had already authorized the development of a new nuclear warhead of low yield but with a shape that would give it a high power to penetrate concrete, the so-called "bunker-busting mini-nuke".
This would have to be tested. If the US resumed nuclear testing, it would give a signal to China to do the same. Other new arrivals to the nuclear club, such as India and Pakistan would use the window of opportunity created by Washington to do the same.
"The danger of a new nuclear arms race is real," Sir Joseph said.
India's declared policy was not to use nuclear weapons first, but if the US made pre-emptive attacks part of its doctrine it would give India the legitimacy to carry out a pre-emptive strike against Pakistan.
Taiwan represented another potential trigger for pre-emptive nuclear strikes by the US and now so too did North Korea, which might already be in possession of two nuclear warheads.
Israel, which kept nuclear weapons and would not allow their acquisition by other countries in the Middle East, had destroyed the Iraqi Osiraq reactor, the first case of a pre-emptive strike on a nuclear installation.
The glaring asymmetry of the US in its relations with Israel and the Palestinians was being exploited by radical groups in the Arab world.
He said: "By utilizing the tremendous advances in technology for military purposes, the United States has built up an overwhelming military superiority, exceeding many-fold the combined military strength of all other nations.
"It is claimed that this is necessary for world security, but actually what such a policy amounts to is to rest the security of the world on a balance of terror."
Arms control, he said, was as good as dead. The only way out of the disaster that lay ahead was to put the goal of total nuclear disarmament back on the agenda.
"We have to convince the public that the continuation of current policies, in which the security of the world is maintained by the indefinite retention of nuclear weapons, is not realistic in the long run, because it is bound eventually to result in a nuclear holocaust in which the future of the human race would be at stake.
"We must convince public opinion that the only alternative is the total elimination of nuclear weapons."
Sir Joseph, Polish-born, was one of the first physicists in Britain to start work on the bomb. He developed the concept of nuclear deterrence before the second world war began, and carried out research on the feasibility of the bomb with James Chadwick in Liverpool in November 1939, two months after the start of the war.
He said: "It was not until much later that I realized the fallacy of the nuclear deterrence concept, but at that time I thought that only by possessing the bomb could we prevent a Nazi victory.
"I did not contemplate and never condoned the use actual use of the bomb. This was the basis for my work in the UK and later on the Manhattan Project in the US."
© Guardian Newspapers Limited 2003