When the Cold War abruptly ended in 1991, Vyacheslav Danilenko was a Soviet weapons scientist in need of a new line of work. At 57, he had three decades of experience inside a top-secret nuclear facility, and one marketable skill: the ability to make objects blow up with nanosecond precision.
Danilenko struggled to become a businessman, traveling through Europe and even to the United States to promote an idea for using explosives to create synthetic diamonds. Finally, he turned to Iran, a country that could fully appreciate the bomb-maker's special mix of experience and talents.
Fifteen years later, the Russian scientist has emerged as a central character in Iran's nuclear program. A report last week by the International Atomic Energy Agency highlighted the role of a "foreign expert"- identified by Western diplomats close to the UN nuclear agency as Danilenko - in Iran's efforts to gain expertise in disciplines essential to building a nuclear warhead.
No bomb was built, the diplomats say. But help from foreign scientists such as Danilenko enabled Iran to leapfrog over technical hurdles that otherwise could have taken years to overcome, according to experts.
Such assistance also provided a trail of evidence that the IAEA's investigators were later able to follow.
Documents and other records - and, in the case of Danilenko, interviews - would offer a rare glimpse inside a highly secretive program hidden within Iranian universities and civilian institutions, the officials and experts said.
For UN investigators, however, the Russian's influence was visible in the design and testing of an unusual, half-sphere-shaped detonator the Iranians perfected eight years ago, shortly after Danilenko left Iran for good.
Danilenko has consistently denied that he ever knowingly aided Iran's nuclear program. "I am not a father of Iran's nuclear program," he told a Russian journalist last week.
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