While military programs rarely capture the attention of the mainstream public, North Korea’s recent string of missile tests helped bring American homeland ballistic missile defense (BMD) to the forefront. Amidst heightened awareness of the nuclear threat, major news outlets picked up on a number of missile-defense-related events, including the deployment of Terminal High Altitude Area Defense (THAAD) batteries to South Korea and the first ever interception of an intercontinental ballistic missile by a Ground-Based Interceptor (GBI). Along with this increased coverage came questions surrounding the effectiveness of American BMD — a matter tackled by publications such as The New York Times. In most cases, mainstream observers assert that homeland missile defenses are not currently effective and probably will not be effective in the near future. The New York Times article, for example, cites GBI’s ostensible 50% success rate and concludes that missile defenses “will not save the country from a North Korean nuclear attack.”

Nobody denies that there are problems with current American missile defenses. The more-ambitious systems — namely, the GBI and the Standard Missile 3 (SM-3) — have less-than-perfect test records and have not demonstrated their capabilities in combat. These are the two systems with the largest coverage and thus the most potential for usage against strategic weapons. Moreover, there are far too few GBIs deployed now to seriously threaten Russian or Chinese deterrent.

However, it is worthwhile to consider the potential for improved performance in the future. After all, long research and development cycles are quite common in the defense industry, and American BMD systems are constantly improving. Though there are a relatively few interceptors deployed at the moment, a drastic ramp-up in production could change the equation going forward.

The problem with assessing American BMD’s potential performance is that most of the relevant information is classified. Given limits of public domain sources, it is worth looking at an unconventional barometer: the actions of American adversaries. Both Russia and China have sophisticated intelligence agencies with analytical capabilities that undoubtedly exceed those of independent defense analysts. As such, the degree to which Russia and China are investing in missile-defense-thwarting technologies can tell us something about how rapidly American missile defenses are progressing and whether they may eventually threaten strategic deterrence.

This perspective problematizes the prevailing narrative that America’s missile defenses have no strategic significance. Russia and China have recently rushed to introduce a number of novel long-range delivery vehicles, all of which are — in some capacity — intended to evade (or entirely negate) missile defenses. In March 2018, Putin held a press conference and discussed a number of “next-generation” weapons: the Avanguard hypersonic glide vehicle (HGV), Kinzhal air-launched ballistic missile, Burevestnik nuclear-powered cruise missile, RS-28 Sarmat heavy intercontinental ballistic missile (ICBM), and Status-6 nuclear-powered underwater vehicle. China has also invested in (and tested) new ICBMs and HGVs. In order to understand how these weapons signal a fear of American missile defenses, it is worth briefly considering their hypothetical capabilities.

The Avangaard HGV is perhaps the most important weapon unveiled by Putin — unlike many of the other systems discussed on March 1st, which are novelties and may or may not see deployment, the Avangard is a feasible weapon with American and Chinese counterparts. Hypersonic glide vehicles are designed to replace traditional ballistic missile reentry vehicles, which follow a ballistic trajectory and cannot perform evasive maneuvers. HGVs, in contrast, generate aerodynamic lift and have control surfaces, allowing them to adopt non-ballistic flight paths and maneuver aggressively at hypersonic speeds (Putin claimed Mach 20 in his address). Traditional missile defense systems rely on the fact that ballistic missile warheads follow a predictable flight path, but Avangard would negate this and be essentially invulnerable to current systems.

China, for its part, recently conducted HGV tests with its new DF-17 ballistic missile, according to DoD intelligence sources. These operational tests, which involved an HGV successfully striking its target, demonstrate a relatively mature capability. Although the DF-17 is an intermediate-range ballistic missile, the HGV itself adds substantial range thanks to its glide capabilities. Moreover, it’s possible that the HGV design tested with the DF-17 could be employed aboard ICBMs as well.

The United States has invested in hypersonic research as well but plans to use the technology for time-sensitive conventional strikes, not BMD evasion.

Russia’s Kinzhal air-launched ballistic missile appears to be an air-launched derivative of the 9K720 Iskander short-range ballistic missile, which features a maneuverable warhead. Not only is the Kinzhal deployed from the MiG-31, an interceptor with an impressive combat radius, but it should also enjoy a range increase over the Iskander thanks to its higher launch altitude and velocity. This gives the Kinzhal+MiG-31 combo a presumptive range in excess of 2,000 km, although the duo would be vulnerable before the Kinzhal is deployed. The weapon would excel in the anti-shipping role, where it could help overcome advanced American defenses such as Aegis BMD. Though Aegis BMD has successfully intercepted traditional anti-ship cruise missiles and ballistic missiles, maneuvering hypersonic threats such as the Kinzhal pose a unique challenge and it does not appear that Aegis BMD has ever been tested against such a threat.

Perhaps the most unorthodox weapon discussed by Putin was the Burevestnik nuclear-powered cruise missile. Scant details are available on this system, which would be the first of its kind ever deployed. Nuclear powerplants are common on large vessels such as submarines and aircraft carriers but have not been particularly successful aboard aircraft. These past failures have been partially due to the weight of the required shielding; of course, cruise missiles have no crewmembers, so radiation leakage is less of a concern. Should the effort prove successful, the resulting missile would have excellent endurance at the expense of high costs and complexity. Since the Burevestnik’s engine would release radioactive materials upon impact, the weapon would likely be restricted to strategic use.

The Burevestnik’s main appeal is stellar survivability in the strategic role. Whereas homeland BMD is proceeding apace, there are no plans to create a comprehensive anti-cruise-missile network for Europe or North America. Due to their high trajectories, ballistic missiles can be countered by a few radars and interceptor bases. In contrast, cruise missiles fly low and slow, complicating detection. Providing persistent defense against a strategic cruise missile attack would require a massive air defense network.

Even though the nuclear cruise missile would be a potent strategic weapon, its cost-effectiveness seems dubious. The Avangard (should it prove successful) would fulfill the same role, fly much faster, be deployable from conventional rocketry, and would not require the development, manufacture, and maintenance of small reactors.

Russia’s much-hyped Status-6 is a long-range, nuclear-powered unmanned underwater vehicle designed to carry a nuclear payload. Such a weapon would have several advantages over the aerial delivery methods commonly employed for nuclear weapons. Bombs and missiles are high-commitment weapons — once they are launched, they cannot be recalled. In contrast, a nuclear underwater delivery vehicle could be maneuvered to its target and loiter there for a considerable period, able to detonate within a moment’s notice. Alternatively, the system could be sent on patrol in the open ocean, where survivability would be all but guaranteed in the event of a nuclear exchange.

Like the other weapons mentioned by Putin, the Status-6 would also bypass current and projected American missile defenses; the ports and harbors of major American cities have no system in place to detect a small, stealthy underwater vehicle like the Status-6 since no threat of this nature existed previously. However, Status-6 development could pose serious engineering challenges, as it would be the first unmanned underwater vehicle with such formidable range and endurance. There is also the potential that American anti-submarine assets or listening posts could detect the system. And, of course, Status-6 would only be useful against coastal targets.

The RS-28 Sarmat, a heavy intercontinental ballistic missile, is the most conventional of Russia’s “next-generation” weapons systems. It is intended to replace older intercontinental ballistic missiles and will be capable of carrying numerous multiple independently-targetable reentry vehicles (MIRVs) and decoys. While existing missile defenses are effective against simple targets, the high quantity of MIRVs combined with numerous advanced decoys could thwart missile defenses by overwhelming them with targets. Since it incorporates pre-existing technologies and reentry vehicles, the RS-28 is certainly less risky than the Avangard and Burevestnik but would be vulnerable to improvements in midcourse discrimination.

It is certainly noteworthy that all these “next-generation” weapons touted by Putin are geared towards thwarting or avoiding BMD. That Russia has relied on traditional ballistic missiles for more than half a century but began developing a number of unconventional delivery systems right as America made key breakthroughs in missile defense is probably not a coincidence. In fact, Putin explicitly mentioned missile defenses as the impetus for the new systems. In contrast, America’s next generation of nuclear weapons will be delivered by conventional ballistic missiles+reentry vehicles, cruise missiles, and bombs. This is not surprising — militaries tend to follow the philosophy of “if it ain’t broke, don’t fix it.” Since Russia’s missile defenses are far less credible than those of the United States, American planners are not concerned with the survivability of their nuclear forces.

In addition to the DF-17 and its associated HGV, China has also taken steps to stay ahead of American missile defenses by introducing the DF-41, a road-mobile ICBM capable of carrying MIRVs and decoys. Like the Sarmat, the DF-41 would present missile defense radars with a large number of potential targets, greatly complicating interception. Chinese defense analysts have publicly stated that the DF-41 is intended to safeguard the PRC’s deterrent against strategic missile defenses. To be sure, China’s new missile systems and HGVs have not been flaunted to the degree of Russia’s new weapons systems. Nevertheless, it does appear that the PRC is quietly incorporating missile-defense-penetrating features into its strategic portfolio.

In summary, it appears that both Russia and China have assessed America’s strategic BMD capabilities as a threat to their deterrence and responded with new weapons systems. This contradicts the prevailing narrative that strategic missile defense is unfeasible and a non-starter. Even though some of the Russian systems are relatively outlandish and may not enter service, the effort invested in developing them to a conceptual stage is nonetheless important. Moreover, that Russia has envisioned such a diverse array of delivery vehicles signals to American officials that they have considered numerous ways in which to thwart future BMD improvements. Of course, it is possible that Russia and China are playing it safe and developing missile-defense-penetrating weapons out of an abundance of caution. However, even this explanation suggests a genuine fear that American ballistic missile defenses could pose a strategic threat, which is more than most missile defense naysayers would grant. Given the formidable intelligence resources of both these American adversaries, their apparent concerns are worthy of consideration in discussions of BMD’s future.