The doomsday scenario of Soviet nukes falling into the hands of rogue states or terrorists has, as far as is known, remained fiction, thanks to a massive U.S.-Russian effort to lock the weaponry up safely after the Soviet Union fell apart.The vast nuclear arsenal, scattered among several newly independent nations, was secured because Russian military officers acted with professionalism and honesty, Moscow and Washington shared clear priorities, and the U.S. taxpayer coughed up billions of dollars, former top officials who dealt with the Soviet nuclear legacy say.
Even so, as the world marks the 20th anniversary of the Soviet demise at the end of 1991, occasional doubts surface about whether the system was airtight. There's the Russian scientist who perhaps went to work for Iran's nuclear program, an old claim that portable nuclear devices went astray, the seizures of smuggled fissile material in the 1990s.
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