Mr.Obama discussed nuclear non-proliferation in the Oval Office Tuesday with former secretaries of state George Shultz and Henry Kissinger, as well as former Defense Secretary William Perry and Sam Nunn, former chairman of the Senate Armed Services Committee.

VOA: standard.2009.05.19

Kissinger and Shultz have joined forces with former Clinton Defense Secretary William Perry and Sen.

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Alan Simpson and William Perry were members of the Iraq Study Group and helped write the panel's report.

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Previously, CIA Director John Deutch was considered the leading contender to replace Defense Secretary William Perry, who has resigned.

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