U.S. Alters Non-Nuclear Prompt-Strike Plan

Tom Z. Collina

Wrestling with an issue that has proven controversial with the U.S. Congress as well as Russia, the Department of Defense has decided not to develop systems for its Conventional Prompt Global Strike mission based on traditional ballistic missiles, according to a Feb. 2 White House report to Congress.

Instead, the report says, the Pentagon will continue to explore “boost-glide” concepts that have a nonballistic flight trajectory, which is deemed less likely to be mistaken for a nuclear attack and would not be counted by the New Strategic Arms Reduction Treaty (New START), which limits only missiles with a ballistic trajectory.

The Pentagon’s interest in a conventional prompt-strike capability stems from the fact that the only weapons in the U.S. arsenal that can reach a target anywhere on the globe in less than an hour are deployed long-range ballistic missiles, all of which are currently armed with nuclear warheads. But using nuclear weapons to attack potential non-nuclear targets, such as leaders of a terrorist group or an adversary’s imminent missile launch, would seem to be inconsistent with current U.S. policy for using such weapons. The 2010 “Nuclear Posture Review Report” states that the “fundamental role” of U.S. nuclear weapons is to “deter nuclear attack on the United States, our allies, and partners.” The report also says that the United States will continue to strengthen its conventional capabilities “with the objective of making deterrence of nuclear attack on the United States or its allies and partners the sole purpose of U.S. nuclear weapons.”

Moreover, the Bush administration argued that the availability of conventional strike weapons could give the president more options in a crisis, reducing the chance that nuclear weapons would be used. A February 2011 report by the National Defense University made a similar point, saying that a conventional strike weapon “might enhance deterrence and assurance by providing an effective and usable (and thus more credible) strike option.”

On the other hand, skeptics such as Sen. Jack Reed (D-R.I.) argue that conventional strike weapons may prove to be unusable as the United States would lack the necessary intelligence to use them quickly against such time-sensitive targets. The time required to verify that intelligence reports were sufficiently credible to justify action would allow the use of other, slower weapons in the U.S. arsenal, such as conventional cruise missiles, they say. For example, they argue, cruise missile-carrying submarines or airplanes could be moved within range of a potential target while breaking intelligence reports were being assessed.

Moreover, according to defense experts, the United States routinely deploys military assets to most “hot spots” where a crisis could be expected to emerge, such as submarines off the coast of North Korea or bombers in Afghanistan. The only regions where the United States might not have such reach would be deep inside large countries with significant air defenses, such as China or Russia. One possible mission for conventional prompt-strike weapons, congressional staffers say, is to be able to knock out Chinese anti-satellite (ASAT) capabilities early in a crisis. China has conducted a series of ASAT tests, most recently on Jan. 11, 2010, according to a Jan. 12, 2010, Department of State cable released by WikiLeaks. “This test is assessed to have furthered both Chinese ASAT and ballistic missile defense…technologies,” the cable said.

The Bush administration had proposed to place conventional warheads on existing Trident II submarine-launched ballistic missiles (SLBMs). Congress blocked that plan in 2008 out of concern that Russia might mistake a conventionally armed strategic missile for a nuclear one and perceive that it was under U.S. nuclear attack. For their part, Russian leaders have said they are concerned that even long-range missiles that are clearly identified as non-nuclear could be used against Russia’s nuclear forces and thus should be considered strategic weapons. During the New START negotiations, Russia initially sought to ban the deployment of conventional warheads on strategic ballistic missiles. The United States rejected this proposal, in part because Congress generally has been supportive of preserving the option for a conventional strike mission.

As a compromise, New START’s preamble states that the parties are “mindful of the impact of conventionally armed ICBMs [intercontinental ballistic missiles] and SLBMs on strategic stability.” The treaty does not prohibit conventional strike systems, but it would count those based on treaty-limited strategic delivery systems, such as the Trident II SLBM and the Minuteman III ICBM, toward the treaty’s ceiling of 1,550 nuclear warheads. During last year’s Senate debate on New START, some Republican senators were concerned that a large deployment of conventional strike weapons would prevent the United States from deploying all 1,550 nuclear weapons allowed by the treaty. To reassure these senators, Secretary of Defense Robert Gates said that if the United States were to deploy treaty-limited conventional systems, they would amount to only a “niche capability.” Gen. Kevin P. Chilton, then the head of U.S. Strategic Command, told Congress that the United States would size a conventional strike force to avoid “perturbing our strategic relationship with Russia and China.”

According to the White House report, a weapons system with a conventional warhead that does not use treaty-limited ICBMs or SLBMs and “does not fly a ballistic trajectory over most of its flight path” would not be counted by New START.

“Boost-Glide”

Addressing some congressional as well as Russian concerns, the Defense Department “at present has no plans to develop or field” conventionally armed ICBMs or SLBMs “with traditional ballistic trajectories,” according to the White House report, which was required by the Senate’s Dec. 22, 2010, resolution of ratification for New START.

Instead, the Pentagon will pursue “boost-glide” systems, which use nontraditional ballistic missiles to “boost” delivery vehicles into space that then “glide” at hypersonic speeds in the upper atmosphere for more than half of their flight. In the United States’ view, these systems would not be limited by New START and could be distinguished by Russia from nuclear-armed missiles.

According to the White House report, the “basing, launch signature, and flight trajectory [of these systems] are distinctly different from that of any deployed nuclear-armed U.S. strategic ballistic missile.”

Unlike U.S. ICBMs and SLBMs, which are based in the central United States and at sea, respectively, boost-glide systems would be based on the coasts, possibly at Vandenberg Air Force Base in California, Cape Canaveral in Florida, or both. Because Russia is “capable of monitoring U.S. ICBM fields, and possibly [SLBM] deployment areas,” according to the report, Moscow could verify that no nuclear launch had occurred. Moreover, says the report, each missile type has a unique infrared signature, and Russia would be able to tell the difference between a Trident SLBM and a missile used for boost-glide, for example.

In addition, Russian early-warning systems can track U.S. launches into space, and boost-glide trajectories look very different from ICBMs or SLBMs. For example, the apogee (highest point) for a boost-glide system is typically less than 100 nautical miles, compared to ICBM or SLBM apogees of 800-1,600 nautical miles, according to the report. Finally, U.S. nuclear-armed re-entry vehicles cannot maneuver as they re-enter the Earth’s atmosphere, but the report says a boost-glide system would, enabling it “to provide precision accuracy and to avoid overflight of selected areas.” However, the report notes that, in addition to providing an observable difference from ICBMs and SLBMs, this maneuverability would give the United States an advantage in carrying out an attack because it adds “an element of uncertainty in terms of impact location.”

According to congressional staff, the boost-glide approach should reduce concerns about Russian misperceptions but not necessarily doubts about the need for the system. There are still significant questions about what the weapon is for, against whom it would be used, and how many would be built and at what cost.

Systems Under Development

The Defense Department has not established an acquisition program for a specific boost-glide conventional-strike system, but is exploring three options: the Hypersonic Technology Vehicle 2 (HTV-2), the Advanced Hypersonic Weapon (AHW), and the Conventional Strike Missile (CSM). For fiscal year 2011, the Obama administration has requested $240 million for a conventional strike program that includes the three options; the Pentagon plans to spend approximately $2 billion between 2011 and 2016 for research and development of these systems.

As part of the Defense Advanced Research Projects Agency’s Falcon program, the Pentagon has been developing two HTV-2s at a cost of $308 million from fiscal year 2003 through 2011. The first flight test took place from Vandenberg in April 2010, and “significant hypersonic flight data was captured,” although the HTV-2 signal was lost only nine minutes into flight, according to the report. The second test is planned for this fiscal year, to be launched from Vandenberg, the report says. The fiscal year ends Sept. 30.

The AHW technology experiment is being run by the U.S. Army Space and Missile Defense Command and Army Forces Strategic Command. It uses a hypersonic glide body that will have an initial flight test at the Kauai Test Facility in Hawaii in late fiscal year 2011 at a cost of $180 million from fiscal year 2006 to 2011.

The U.S. Air Force Space and Missile Systems Center runs the CSM program, the leading contender for the conventional strike mission. Under the current schedule, the CSM program will have a first flight demonstration at Vandenberg in fiscal year 2013 using a kinetic energy projectile (KEP) warhead at a cost of $477 million from fiscal year 2008 to 2013. The report says that an operational CSM could provide “complete global coverage of potential targets” from Vandenberg. The KEP warhead would “neutralize the target” by delivering thousands of “high density, cube-shaped metal fragments” at high speed, the report said.

“New” Strategic Arms?

Although boost-glide systems would not count as existing strategic weapons under New START, they could qualify as “new” kinds of strategic offensive arms, according to an October 2010 report by the Congressional Research Service. As a result, Russia could raise the issue of whether future boost-glide systems should count under the treaty. Nevertheless, the United States would not have to delay its boost-glide programs while such discussions are underway, even if Russia ultimately were to disagree with a U.S. decision to proceed with these systems. The United States would be obligated to try to resolve the issue within New START’s Bilateral Consultative Commission, but, according to the State Department’s article-by-article analysis of the treaty, “there is no requirement in the treaty for the deploying party to delay deployment of the new system pending such resolution.”

The Russian legislature disagrees. According to Russia’s resolution of ratification for New START, questions about new kinds of strategic offensive arms should be resolved within the consultative commission “prior to the deployment of" such new strategic weapons.