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"Bunker Busters": Robust Nuclear Earth Penetrator Issues, FY2005 and FY2006

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Congressional rept.

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Potential adversaries and others have built hardened underground facilities to protect key assets. Conventional weapons are unable to destroy many such facilities, though opinions differ on whether non-nuclear means can disable or isolate them. Surface-burst nuclear weapons would have limited effectiveness against such facilities. In contrast, a weapon that burrows into the ground a few meters before detonating would be more effective because it would transfer much more of its energy into the ground. Accordingly, the Department of Defense DoD and the National Nuclear Security Administration NNSA, the Department of Energy DOE agency in charge of the U.S. nuclear weapons program, have requested funds to study the Robust Nuclear Earth Penetrator RNEP. RNEP has been the most controversial nuclear weapon program in Congress for the last several years. Supporters argue that it is needed to attack hard and deeply buried targets such as leadership bunkers in countries of concern, thereby deterring or defeating challenges from such nations critics assert that RNEP would lower the threshold for use of nuclear weapons and prompt other nations to develop nuclear weapons to deter U.S. attack. For FY2003, Congress provided 15.0 million as requested, but for FY2004, it reduced the request from 15.0 million to 7.5 million, and for FY2005 it eliminated RNEP funding. For FY2006, the Administration requests 4.0 million for NNSA and 4.5 million for DoD to study RNEP. This report presents a brief technical background on RNEP, then discusses the history of RNEP in Congress and the Administration for the FY2005 and FY2006 budget cycles. For a more extensive history and technical background, see CRS Report RL32130, Nuclear Weapon Initiatives Low-Yield RD, Advanced Concepts, Earth Penetrators, Test Readiness and CRS Report RL32599, Bunker Busters Sources of Confusion in the Robust Nuclear Earth Penetrator Debate, both by Jonathan Medalia.

Subject Categories:

  • Economics and Cost Analysis
  • Government and Political Science
  • Nuclear Weapons

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