WASHINGTON -- A new report warns that future U.S. nonnuclear rapid-strike arms could pose a little-understood risk of crossing tripwires to global conflict if a major military power could not determine whether it is being targeted in a quickly unfolding attack.
“Non-ballistic CPGS weapons, which are highly maneuverable, could possibly lead an observing state to wrongly conclude that an incoming weapon was heading for its territory,” states a Carnegie Endowment analysis, explaining how so-called “conventional prompt global strike” arms might pose what it terms “destination ambiguity.”
A foreign nation with advanced early-warning intelligence capabilities -- such as Russia fields today and China may have in the future -- also might be uncertain whether a U.S. maneuverable, fast-strike weapon is on the verge of taking out its own atomic weapons, according James Acton’s report, “Silver Bullet? Asking the Right Questions About Conventional Prompt Global Strike.”
“A state could mistakenly believe that its nuclear forces were under attack when its conventional forces were really the target,” a situation that the author calls “target ambiguity.”
“This situation could arise, for instance, if a state’s nuclear and conventional assets were ‘entangled’ because of dual-use command-and-control systems,” he writes.
The risks of such misunderstandings could run high, he says.
“A state that feared its critical weapon systems -- particularly nuclear weapons -- were vulnerable to a preemptive CPGS strike could feel pressure to use or threaten to use those weapons first, [creating] crisis instability,” according to the report.
Acton, a senior associate in Carnegie’s Nuclear Policy Program, argues that while there has been much debate on Capitol Hill about potentially destabilizing aspects of deploying and using conventional prompt-strike weapons, concerns have focused too much on warhead ambiguity when a broader set of pressing issues should be addressed.
U.S. lawmakers in past years rejected a concept for conventional prompt global strike that would have swapped out nuclear warheads for conventional front ends on Trident D-5 submarine-based ballistic missiles. They cited concerns that Russia or China might someday detect a U.S. Trident launch and, unaware which type of warhead the missile carried, could respond precipitously with atomic arms.
With the “Conventional Trident Modification” effort put on the back burner, warhead ambiguity is no longer the most pressing crisis-stability issue facing the development of prompt-strike weapons, Acton argues.
An array of technological alternatives remains for the nonnuclear prompt-strike mission. Those include:
-- The Army’s Advanced Hypersonic Weapon, a futuristic capability that, if technically feasible, could be either land- or sea-based;
-- The Hypersonic Technology Vehicle-2, developed by the Defense Advanced Research Projects Agency but recently put back into risk-mitigation after test failures;
-- A Navy Sea-Launched Intermediate Range Ballistic Missile, which Acton reports could carry either a hypersonic glider or steerable reentry vehicle, but which recently experienced some bureaucratic setbacks; and
-- An Air Force High Speed Strike Weapon, an air-launched hypersonic cruise missile that Acton describes as being developed outside of the prompt global strike program.
Acton urges the Defense Department to fully explore the prospective strengths and drawbacks of each option, keeping in mind that each alternative may pose less risk of one kind of ambiguity during a crisis while aggravating ambiguity in another way.
“The most discussed strategic risk is the possibility that a CPGS weapon could be mistaken for a nuclear weapon,” states the physicist in the 197-page document. “Other escalation risks are, however, more serious.”
As Acton explains it, “An observing state might mistakenly believe that a CPGS weapon was heading for its territory, not only exacerbating the risk of warhead ambiguity but also creating new risks of escalation.”
The report’s bottom-line recommendation for the Pentagon is “to look at the question of CPGS acquisition holistically,” the scholar told Global Security Newswire in an e-mailed response to questions.
“On the one hand, there is a very plausible argument that CPGS weapons will enhance deterrence and make war less likely,” he said. “On the other hand, the potential escalatory implications of boost-glide weapons have been neglected.”
Though Pentagon officials discuss an array of counter-terrorism and counter-proliferation targets that might be the focus of nonnuclear prompt-strike weapons, the Defense Department has not formally determined for what missions these arms would be procured, he states in the report.
Beyond the stubborn ambiguity challenges, “there are questions about the military utility of candidate CPGS technologies, especially in the absence of needed enabling capabilities,” he told GSN, referring to command-and-control systems; intelligence, surveillance and reconnaissance requirements; and post-attack battle damage assessment systems.
“And,” Acton said, “there needs to be a comparison of whether non-prompt alternatives might be more cost effective.”