Hypersonics in enemy hands are immeasurable threat to America

Hypersonics in enemy hands are immeasurable threat to America
© Getty Images

In the movie “The Graduate,” the older and wiser Mr. McGuire puts his arm around young Ben Braddock's shoulders and offers one word of advice about the future: “Plastics.” If the same scene took place today, he would solemnly intone: “Hypersonics. They’re the future.”

Or are they? Hypersonic weapons are an emerging threat, but what kind of threat remains unclear. In recent testimony to Congress, Stratcom commander Gen. John Hyten described a hypersonic weapon as “like a ballistic missile, but then it depresses the trajectory and then flies more like a cruise missile or an airplane. So it goes up into the low reaches of space, and then turns immediately back down and then levels out and flies at a very high level of speed.”

The missiles can carry both nuclear and conventional payloads. Such weapons can have many uses, and lumping them all together under one catch-all phrase isn’t very helpful in figuring out what kind of threat they pose to U.S. national security. They can be used for reconnaissance, for destroying a range of enemy assets far from home (and far from a battlefield), and they could even be used to deliver a nuclear sucker-punch.

This is why Russian President Vladimir Putin looked so pleased when he recently unveiled an amateurish video of a “nuclear cruise missile” (a weapon he probably doesn’t have) — because a fast, long-range, undetectable weapon could destroy an enemy capital or multiple enemy targets with literally no warning at all.

If the concern is that America’s near-peers have developed a hypersonic capability to deliver nuclear weapons, then this isn’t all that new of a problem. ICBMs and their sea-launched alternatives, SLBMs, already travel at hypersonic speeds. (A “hypersonic” vehicle would be tough to catch at Mach 5, but an ICBM warhead comes in at Mach 23.) In terms of the strategic balance of power, this doesn’t mean very much: A nuclear bomb landing on a U.S. target is still a nuclear bomb landing on a U.S. target.

Missile-defense advocates could claim that these weapons take an existing problem that is already a major challenge — that is, defending the United States against a strategic nuclear attack — and make it practically an insoluble problem. This aspect of the hypersonic problem, however, is overblown.

Even during the Cold War, U.S. strategists worried about the vulnerability of coastal targets to submarine-launched missiles on a depressed trajectory. Washington, Honolulu, New York, Los Angeles or Seattle would have less than a few moments of warning, if any, before they were destroyed.

As a nuclear delivery system, hypersonic weapons would not change much in the strategic equation, especially among strategists (like me) who do not think national missile defenses will ever be capable of stopping any sizable attack against the United States. It is true that the United States has no ability to defend against hypersonic weapons. But, then, it has no ability to defeat any other kind of intercontinental missile attack, either.

In other uses, however, hypersonics could pose a qualitatively new threat to U.S. and allied security. Hypersonic reconnaissance vehicles could provide major advantages to the side that masters them and cause major headaches for the side that can’t spot them or shoot them down. At the theater level, hypersonic weapons could mean qualitatively new complications in security planning.

National missile defenses might not be within reach, but theater-level defenses — those that guard against launches from short-range or intermediate-range missiles — have at least some chance of effectiveness. The creation of unstoppable and undetectable theater weapons that can evade both detection and countermeasures is a serious problem.

Again, however, there is an irony here that if these vehicles are armed with nuclear weapons, the deterrence calculus is actually somewhat less complicated. A nuclear attack is a nuclear attack. How the bomb gets to where it’s going is less important than the decision to cross the line into nuclear use and, thus, risk escalation and global destruction.

If these hypersonic weapons, however, are armed with conventional munitions, things get very complicated indeed. The ability to destroy large military assets — without detection and at high speed — could induce immense confusion and critical lags in the ability to respond. These effects could be so destructive that they would mimic the effects of nuclear use, without the actual risk of employing nuclear weapons.

This is probably the chief reason Russia and China are so interested in hypersonic weapons. While they would do little to change the overall deterrent relationship between the United States and its nuclear-armed peers, they could provide an edge in a regional conflict in ways that previous U.S. strategists have never confronted.

What can the United States do? One important step, in addition to existing programs of testing, is to avoid any further conceptual confusion about “hypersonics.” They are not a single class of system, and they are unlikely to change the balance of power or upset the existing strategic nuclear deterrent situation.

But they can, if unchecked, lead to operational and theater-level problems that could, in turn, open the door to conflicts that could progress to immeasurably dangerous consequences. The threat isn’t here yet, but it’s on the immediate horizon.

Tom Nichols is a professor of national security affairs at the U.S. Naval War College and an adjunct professor at the Harvard Extension School. His latest book is “The Death of Expertise: The Campaign Against Established Knowledge and Why It Matters.” You can follow him on Twitter @RadioFreeTom. The views expressed in this column are his own.