Another sphere in which our diplomacy depends on the input of the agencies is in defeating weapons proliferation. The proliferation of weapons of mass destruction is one of the greatest menaces to global peace. The task of defeating proliferation becomes technically more challenging as the technology spreads and the cost declines. Nor is the problem confined only to warhead technology. The spread of missile technology has introduced a new threat of more sophisticated delivery systems.
Policy making on proliferation depends to an unusually large degree on secret intelligence.
I sometimes find a common assumption that, in the age of satellite surveillance, we can acquire all the information that is necessary by technical means. Sadly, that faith in high technology is misplaced. Human intelligence is essential in identifying a threat of proliferation, especially of biological and chemical weapons, the production of which can so easily be disguised as industrial process. Without human agents, we could not take effective measures to disrupt or prevent proliferation. There is one other way in which the product of our intelligence agencies is crucial to our foreign policy.