There's a long record here of being wrong. There's a good reason for it. There are probably multiple reasons. Certainly proliferation is a hard thing to track, particularly in countries that deny easy and free access and don't have free and open societies. ↗
When we think of the major threats to our national security, the first to come to mind are nuclear proliferation, rogue states and global terrorism. But another kind of threat lurks beyond our shores, one from nature, not humans - an avian flu pandemic. ↗
We've already seen proliferation. We started it with Britain, then France. Then we benignly let the Israelis do it. The Pakistanis and the Indians have recently done it. The Chinese have nuclear weapons. ↗