Measurement approaches to support future warhead arms control transparency

Transparency on warhead stockpiles, warhead dismantlement, and fissile material stockpiles in nuclear weapons states will become increasingly important in the move beyond START II toward lower quantities of warheads. Congressional support for further warhead reductions will likely depend on the degree of irreversibility, or in other words, the rapidity with which warhead inventories could be reconstituted. Whether irreversibility considerations can be satisfied will depend on monitoring dismantlement as well as constraining the available stockpile of fissile materials for possible refabrication into warheads. Measurement techniques designed to address the above problems will need to consider NPT Article 1 obligations as well as Russian and US classification regulations, which prohibit or restrict the transfer of nuclear warhead design information to other states. Classification considerations currently limit the potential completeness of future inspections of weapons materials. Many conventional international safeguards approaches are not currently viable for arms control applications because they would reveal weapons design information. The authors discuss a variety of technical measures that may help to improve transparence of warhead and fissile material stockpiles and may enable limited warhead dismantlement transparency.