Single Integrated Operational Plan (SIOP)

The U.S. strategic warfighting plan for the use of nuclear weapons. The Single Integrated Operational [Page 659]Plan (SIOP) is one of the most highly classified of all government documents.

The SIOP is the culmination of a long process that begins with the president of the United States, who provides the U.S. Department of Defense (DoD) with a conceptual guide for the use of nuclear weapons. The DoD converts that information into the Nuclear Weapons Employment Policy, a list of objectives, specific targets, and operational constraints. The Joint Chiefs of Staff then rework that list into the Joint Strategic Capabilities Plan. The U.S. Strategic Command uses the Joint Strategic Capabilities Plan to compile the SIOP, which contains the specifics of targeting orders, scheduling, and needed weapons. A new SIOP is approved each year, even if it is not fundamentally different from the previous year's plan.

The first SIOP was approved in late 1960 as an attempt to develop a more systematic approach to the various targets for potential U.S. nuclear strikes. It was also a response to advances in technology that improved the U.S. ability to hit a broader range of targets. Recently declassified documents indicate that outgoing President Dwight D. Eisenhower and other top officials believed that the first SIOP went too far. The plan called for multiple nuclear strikes against military and urban-industrial targets in the Soviet Union, China, and their allies. The initial SIOP also tried to unite the various nuclear forces of the U.S. Air Force, Navy, and Army into a synchronized format.

Since those early years, various SIOPs have been developed. SIOPs focused on counter-force strategy from the early to mid-1960s, deterrence and more flexible responses with limited nuclear options in the mid-1970s and early 1980s, and again on counter-force strategy in the mid-to late 1980s. The number of targets has dropped dramatically since the collapse of the Soviet Union in 1991.

The existence of SIOP was not publicly acknowledged for more than a decade, and many details about SIOP remain shrouded in mystery. From the beginning, a special information category—extremely sensitive information (ESI)—has been attached to the SIOP. The U.S. government is understandably cautious about revealing details of its nuclear strategy, even though some observers feel that American citizens should be aware of their country's nuclear intentions.