When North Korea commits a provocation, the U.S. often responds by conducting a flyover with its strategic bombers. American bombers flew over South Korea after both of Pyongyang’s recent intercontinental ballistic missile tests this month as well as nuclear tests in previous years.
Strategic bombers can display American power and its resolve to defend allies. But this message of deterrence only works when it is credible. For this reason, the United States is developing a new stealth bomber called the B-21 Raider and a new nuclear-tipped cruise missile known as the Long Range Standoff missile (LRSO). These programs will add versatility to the strategic bomber leg of America’s nuclear triad.
Strategic bombers serve a unique and essential role in the triad, because they are capable of a flexible response to a potential nuclear attack. Unlike ground-launched and submarine-launched ballistic missiles, bombers can be easily recalled mid-flight. According to retired Air Force Lt. Gen. David Deptula, “[Bombers] can signal U.S. concern and resolve in crises by providing options that include: placing the bomber force on alert; dispersing the bomber force; and/or conducting shows of force,” and unlike ICBMs or ballistic missile submarines, can do so with a low risk of escalation.
Bombers can carry gravity bombs or cruise missiles, and this versatility adds to their deterrent value by increasing the threats an adversary would have to defend against. The U.S. Air Force currently flies the B-52, B-1B, and B-2, though the B-1B is not currently configured to carry nuclear ordnance. The B-21 is expected to enter service beginning in 2025 and will fly alongside—and eventually replace—all three bombers currently in use.
The B-21 Raider, named after the Doolittle Raiders—the WWII U.S. bomber group that conducted a surprise attack against the Japanese mainland by launching from an aircraft carrier—will draw together decades worth of experience and advancements in stealth and electronic warfare technologies to create the world’s most advanced stealth bomber. Moreover, its design will incorporate a flexible architecture to accommodate future technologies so that it can stay ahead of enemy countermeasures.
These technologies are so advanced the government considers them to be a state secret, and therefore the total cost of the program is not publicly available. Current estimates place the unit cost of each of the 100 planned B-21s at $564 million in FY2016 dollars.
Though the Air Force intends to procure 100 B-21s, many experts believe this number is too low. Former Secretary of the Air Force Deborah Lee James told The Cipher Brief that “there could be more than 100, and what we need to do is revalidate that requirement given current world conditions.” Russia and China are undertaking their own nuclear modernization and stealth bomber development programs, and the Pentagon is currently in the midst of its Nuclear Posture Review to determine America’s future needs for its nuclear triad.
Also under consideration in the Nuclear Posture Review is the fate of the LRSO. Though still in the planning stages, the LRSO is expected to be a stealthy cruise missile with a 2,000-mile range that could be fired from the B-52, B-2, F-35, and eventually the B-21. Deptula explained the LRSO’s mission as such: “…because of its characteristics of small size and signature, range, and speed, LRSO will enable the expansion of simultaneity of attack across the breadth and depth of adversary geography significantly complicating the adversary’s defense calculus.”
The LRSO is under fire because advocates of minimal nuclear deterrence question whether its added capabilities and program cost—between $17 and $20 billion for 1,000 missiles— are necessary. Moreover, they argue that its capabilities will compel adversaries to develop similar weapons and create instability rather than deter it.
Proponents of the LRSO maintain that canceling the program is unlikely to cause adversaries to abandon their own programs, and without the LRSO, the B-52 would be too vulnerable and rendered obsolete decades sooner than planned. They argue the B-21 armed only with gravity bombs would be what Mark Schneider, a senior analyst at the National Institute for Public Policy, called “a sixth generation bomber delivering a 1960s vintage nuclear bomb with a 1990s vintage JDAM tail kit,” in a recent article for Real Clear Defense. If LRSO development continues, it will likely enter service in 2030.
The B-21 and LRSO have the potential to greatly improve the flexibility of the strategic bomber leg of America’s nuclear triad, yet their high cost, long development times, and the unpredictability of future events mean their future success is uncertain. The B-2 serves as a cautionary tale. Designed during the Cold War, the original plans called for 132 bombers, though the fall of the Soviet Union precipitated a slash in defense spending, resulting in only 21 B-2s entering service at a total program cost of nearly $2 billion per aircraft.
Whatever the future brings, as long as adversaries possess or strive for the capability to strike the United States with nuclear weapons, the U.S. will pursue an advanced nuclear triad to maintain a credible response for deterrence.
This feature is the second part in a two-part series on America’s new nuclear triad. For part one on the Columbia Class ballistic missile submarine and the next generation ICBM, click here.
Will Edwards is an Asia-Pacific and defense analyst at The Cipher Brief. Follow him on Twitter @_wedwards.