In 1997 the U.S. Department of Energy (DOE) accepted the "stored weapons standard" for the U.S. weapons-usable fissile material (both plutonium and highly enriched uranium) in the DOE's inventory. The DOE material to be subject to the standard includes material in the DOE's ultimate material disposition program; excess but not yet designated for disposition; and to be retained for national defense. The security standard assumes a violent, external assault by a group using weapons and vehicles, possibly with inside assistance. Specific requirements for protection against such a threat include a strong, secure storage vault with a single entry surrounded by two layers of strong fences and an open, lighted area where no one could hide. Access to the vault should be limited to personnel with a need for access, who are cleared through full-field background investigations and accompanied by another such person. Such access limitations should be enforced by both armed guards and electronic monitoring devices, supported in case of need by nearby armed backup forces. All of these personnel should be trained to deal with design-basis threats, and their competence should be checked periodically in exercises comparable to war games. This paper compares these security measures with the two most relevant international standards for comparison: the Convention on the Physical Protection of Nuclear Materials of 1980 and the International Atomic Energy Agency's guidelines for physical protection. These international standards are generally more lax than U.S. standards. This paper describes efforts to upgrade the international standards. 28 notes and appended description of "stored weapons standard" for protecting weapons-usable fissile material