Nobody is certain what Sultan Bashiruddin Mahmood has been up to in Afghanistan in the past three years--but nobody in the West much likes it either. Mahmood is one of Pakistan's leading nuclear engineers, a key part of the team that developed the country's small arsenal of atom bombs. According to a lot of people, he also may be a little flaky. The fact that since 1998, so loose a nuclear cannon has been traveling in and out of the Taliban stronghold of Kandahar, where he has helped the Afghans construct a complex of buildings he describes as flour mills, has a lot of people worried.
It was for this and other reasons that Pakistan detained Mahmood and two of his colleagues to determine if the three scientists may have been passing nuclear expertise, raw materials or--worse--functioning weaponry on to the Taliban. So far, nothing Islamabad has learned has proved that the men have indeed been trafficking in secrets, and they have been released. But nothing has put all doubts to rest either.
The detention of the three scientists was just the latest in the so-far offstage effort to battle the most dreadful of the terror weapons Osama bin Laden would like to have in his arsenal: nuclear arms. Airborne anthrax and hijacked planes are little more than a murderous tease compared with the prospect of rogue nukes. Just what bin Laden has in his stockpiles, what he plans to do with it and what can be done to stop him are rapidly becoming the most pressing questions in the anti-terror wars. "The goal of terrorism is to spread panic," says Dr. Jerrold Post, a physician and professor at George Washington University's Elliott School of International Affairs, who believes that al-Qaeda would try a nuclear or radiological attack if it had the capacity. "Psychologically, there are no constraints."
It's been an open secret in the intelligence community that bin Laden and his al-Qaeda organization have long lusted after nukes. The consensus in Washington is that the group does not have a true nuclear-fission device, though it may well have what is known as a radiological weapon or "dirty bomb"--a conventional explosive packed with radioactive debris. Whatever bin Laden's got, he has made any number of attempts to get more. As early as the mid-1990s, intelligence sources tell TIME, bin Laden's agents began cruising the black markets of Europe and Asia looking for pirated Russian warheads. Al-Qaeda also made it known that loose components such as enriched uranium would do too. Relatively new to the free-for-all thieving of the post-Soviet republics, bin Laden was fleeced at least twice, getting fooled by black marketeers who tried to sell him low-grade, radioactive rubbish--in one instance claiming it was "red mercury," a fictional Russian weapon.