Nevertheless, during the sixty years of the twentieth century many problems have come increasingly into the realm of acceptable public discussion.

Clearly, the first task is to gain acceptance of a more reasonable view of the future, one that opens possibilities rather than forecloses them.

There was no race - but to the extent that there was an arms competition, it was almost entirely on the Soviet side, first to catch up and then to surpass the Americans.

In a world which is armed to its teeth with nuclear weapons, every quarrel or difference of opinion may lead to violence of a kind quite different from what is possible today.

Anything that reduces war-related destruction should not be considered altogether immoral.

From a scientific perspective there is some indication that a nuclear war could deplete the earth's ozone layer or, less likely, could bring on a new Ice Age - but there is no suggestion that either the created order or mankind would be destroyed in the process.

My guess is that nuclear weapons will be used sometime in the next hundred years, but that their use is much more likely to be small and limited than widespread and unconstrained.