From an article by Sidney N. Graybeal and Michael Krepon in Bulletin of the Atomic Scientists (December):

On-site inspections can be of substantive value while serving as a powerful symbol of the improved cooperation needed if new arms reduction agreements are to succeed. These benefits, however, will be lost if cooperation is lacking. Inspections can resolve disputes over ambiguities only when both parties wish to do so. When parties do not fully support the objectives and purposes of an agreement, inspection provisions can become a visible symbol of failure instead of cooperation. . . .

Routine inspections at declared production, deployment and test areas, if properly devised and implemented, will modestly increase confidence in compliance without compromising intelligence sources and methods. In contrast, challenge inspections of suspect sites are unlikely to build confidence in compliance or to deter violations since there are many ways a determined cheater can avoid a thorough or timely inspection and can deflect the political repercussions of doing so. Invitational inspections offer an alternative to challenge inspections when compliance questions arise. Invitational site visits can defuse politically sensitive issues but can also be misused.

Unfortunately, the utility of inspections has been greatly oversold politically -- a situation that is fraught with danger if future agreements depend upon this uncertain mechanism. In light of the limited U.S. experience with on-site inspections and their modest utility, dependence on highly intrusive monitoring should initially be kept at a minimum. In the final analysis, strict compliance can best be maintained by a common desire to reap the benefits of an agreement.