It is awesome to consider nightmare scenarios such as Mr. Perle has proposed. The overriding aim of our strategic nuclear policy must be to see that they never become reality. No one likes the idea that our defense rests on the threat of genocide. But no one has yet devised a more effective deterrent. Mr. Perle’s suggestions ultimately rest on technological breakthroughs which may or may not happen. However, I do agree that the lessons of SALT I should be borne in mind when making predictions about the outcome of SALT II.