Prompt Global Strike

Prompt Global Strike (PGS) is a United States military effort to develop a system that can deliver a precision-guided conventional weapon airstrike anywhere in the world within one hour, in a similar manner to a nuclear ICBM. Such a weapon would allow the United States to respond far more swiftly to rapidly emerging threats than is possible with conventional forces. A PGS system could also be useful during a nuclear conflict, potentially replacing the use of nuclear weapons against 30% of targets. The PGS program encompasses numerous established and emerging technologies, including conventional surface-launched missiles and air- and submarine-launched hypersonic missiles, although no specific PGS system has yet been finalized as of 2015.

The PGS system is intended to complement existing American rapid-response forces, such as Forward Deployed Forces, Air Expeditionary Groups (which can deploy within 48 hours) and carrier battle groups (which can respond within 96 hours). Possible delivery systems for PGS warheads include:

In 2010, the United States Air Force prototyped a PGS system based on a modified Minuteman III ICBM. In March 2011, Air Force Major General David Scott stated that the service had no plans to use a sea- or land-based ICBM system for Prompt Global Strike, as they would be expensive to develop and potentially "dangerous." Instead, efforts would focus on a hypersonic glider. However, the following day, Chief of Staff of the United States Air Force Norton Schwartz said that an ICBM-based PGS system was still an option.

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