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However, Mark Dubowitz, executive director of the Foundation for the Defense of Democracies, a hawkish Washington think tank, said: "Designing sanctions to make Khamenei relent in his 30-year quest for a nuclear weapon is a delusion."
Advocating using sanctions to help bring regime change in Tehran, Mr. Dubowitz said Iran's clerical leaders see a potential nuclear weapon as "a guarantee of regime survival."
"There is no evidence to date that the supreme leader employs a risk-reward calculus in making decisions about the nuclear program," he said.
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