An independent panel recently provided a boost to a coolly received Pentagon initiative that would convert some long-range, submarine-launched ballistic missiles to deliver conventional warheads instead of nuclear ones.
In a May 11 report to Congress, the 19-member panel of the National Academy of Sciences (NAS) National Research Council stated the initiative, if proven effective, “would be a valuable addition to U.S. military capabilities.” The initiative is intended to enable the United States to conduct non-nuclear strikes worldwide in less than an hour.
The general concept is known as prompt global strike. Under the Conventional Trident Modification program, each of the dozen deployed U.S. ballistic missile submarines would have two of their 24 Trident nuclear-armed ballistic missiles converted to carry conventional payloads.
The panel recommended that lawmakers sufficiently fund research and development of the program so an “initial operational capability” will be ready in three years. But it also urged postponing full-scale production and deployment until some policy issues are settled.
The experts said policymakers should explore alternatives and deal with the “ambiguity issue,” which is the possibility that other countries, particularly Russia, might mistake a conventional Trident launch as a nuclear attack. This danger has been a central concern of lawmakers, leading them last year to cut inaugural funding for the program from $127 million to $25 million and commission the NAS study. The Bush administration asked Congress in February for an additional $175 million. (See ACT, April 2007. )
Congressional caution toward the program remains widespread. On May 17, the House passed a fiscal year 2008 defense authorization bill that prohibits any spending to deploy conventional Tridents. Rep. Ellen Tauscher (D-Calif.), who chairs the House Armed Services Strategic Forces Subcommittee, which initially proposed the restriction, said the move reflected a “need for additional effort to ensure that a conventional missile launch from a Trident submarine is not misinterpreted.”
The Senate has yet to pass its version of the defense authorization bill, which will then need to be reconciled with the House measure, but some senators share similar sentiments. At an April 11 hearing, Senate Armed Services Chairman Carl Levin (D-Mich.) said the proposed conversion “is a very destabilizing idea in the minds of many of us.”
The NAS panel suggested that “cooperative measures” with other countries might help reduce misunderstandings and recommended that any prompt global strike effort, including the Trident conversion, “be designed in both hardware and operational terms to minimize the possibility of misinterpreting intent.” Yet, the panel noted, “the ambiguity between nuclear and conventional payloads can never be totally resolved.”
Still, the experts asserted that a prompt global strike capability is worth pursuing. “Given the pace of terrorism’s spread and the consequent uncertainty about where terrorist operations will occur, coupled with the proliferation of weapons of mass destruction, a truly global capability may soon be required, if it is not required today,” the panel stated.
In addition to being used against terrorists, the panel said prompt global strike systems could be employed at the outset, or “leading edge,” of major combat operations. In such a scenario, the panel cautioned that misinterpretation risks would rise.
The brief time frames associated with prompt global strike also present difficulties, according to the panel. It stated that getting accurate and reliable short-notice data on a target would be a “daunting challenge” and warned that decision-makers would have to rapidly weigh potential collateral damage and other risks.
The panel predicted that the actual use of prompt global strike weapons would be rare, numbering “at most a few dozen” instances during their first decade of service. It calculated that “only a few terrorist leaders would merit use of such a weapon.”
Other prompt global strike options mentioned by the panel include conventionally armed U.S.-based ICBMs, intercontinental-range hypersonic boost-glide vehicles, and higher-speed cruise missiles launched from bombers. These and the Trident conversion program will be analyzed more fully in a second report the panel is supposed to supply Congress early next year.
Albert Carnesale, who most recently served as chancellor of UCLA, chairs the panel. Other panel members include retired General Eugene Habiger, former commander of U.S. Strategic Command; James Woolsey, former head of the Central Intelligence Agency; and Walter Slocombe, former undersecretary of defense for policy.
Corrected online September 3, 3008. See explanation.