At the Massachusetts Institute of Technology in the mid-1970s, Ernest J. Moniz was an up-and-coming nuclear scientist in search of tenure, and Ali Akbar Salehi, a brilliant Iranian graduate student, was finishing a dissertation on fast-neutron reactors.
The two did not know each other, but they followed similar paths once they left the campus: Mr. Moniz went on to become one of the nation’s most respected nuclear physicists and is now President Obama’s energy secretary. Mr. Salehi, who was part of the last wave of Iranians to conduct nuclear studies at America’s elite universities, returned to an Iran in revolution and rose to oversee the country’s nuclear program.
You may read more about it in the article. And I definitely agree with this sentiment:
Mr. Moniz, 70, understands his role well: He is providing not only technical expertise but also political cover for Mr. Kerry. If a so-called framework agreement is reached in the next few days, it will be Mr. Moniz who will have to vouch to a suspicious Congress, to Israel and to Arab allies that Iran would be incapable of assembling the raw material for a single nuclear weapon in less than a year.“It wouldn’t mean much coming from Kerry,” said a member of the administration deeply involved in the strategy who spoke on the condition of anonymity. “The theory is that Ernie’s judgment on that matter is unassailable.”
At the heart of this is a scientific/technical issues. Now once presented, it is up to the politicians to decide, because beyond that, it is no longer a science/technical decision, but a political one. To have someone, a negotiator, who is not only knowledgeable in that area, but also who happens to be a world-renowned expert, is extremely beneficial.