Putting hype in hypersonic

Hypersonic missiles are not terrifying new weapons. They are just another cog in the terrifying stable strategy called nuclear deterrence.

“The Avangard hypersonic glide vehicle entered service at 10am Moscow time on December 27,” boasted Russian Defence Minister Sergei Shoigu – and nobody quailed in their boots.

The new missile can deliver nuclear weapons, of course, and the Russians are very proud of it. As President Vladimir Putin said: “Not a single other country possesses hypersonic weapons, let alone continental-range hypersonic weapons.” They’ll all be green with envy.

A hypersonic missile’s warheads launch on a rocket, just like the traditional intercontinental ballistic missiles (ICBMs). However, instead of going very high and travelling most of the distance through space in a predictable ballistic trajectory before plunging back down into the atmosphere and striking their target, the hypersonic missile’s warheads go low early.

The missile launches on a depressed trajectory and then a “glide vehicle” detaches from the rocket and skips along the edge of the atmosphere, travelling at up to 20 times the speed of sound. It only becomes visible to the enemy’s radar when it is close to the target.

Even better, it can manoeuvre on the way in to its target, which makes it hard to intercept. As Putin proudly said: “It is invulnerable to intercept by any existing defence.” Indeed, he said, everybody else is “playing catch-up with us.”

This would be deeply alarming to Russia’s potential adversaries if all the orthodox, traditional ICBMs had suddenly become vulnerable to interception. Then, only the Russians would have missiles that could get through the other side’s defences and so they would rule the world. But, in fact, there are no effective defences against mass attacks by conventional ICBMs.

The US has been working on anti-ballistic missile (ABM) systems since Ronald Reagan’s “Star Wars” almost four decades ago. It might stop one or two incoming ICBMs launched by, let’s say, North Korea. But it couldn’t stop the hundreds of ICBMs Russia would launch in a nuclear war.

The problem with any kind of anti-missile defence system is that it’s relatively cheap and easy to overwhelm it by sheer numbers. Hypersonic missiles are wonderfully fast and clever, but they’re also expensive and quite unnecessary.

So, why has Russia spent what is clearly a great deal of money to develop a snazzy, but pointless, weapon? Because the “metal eaters’ alliance”, the Russian equivalent of the US “military-industrial complex”, is still kicking despite the demise of the old Soviet Union. Developing new weapons is what it does, whether they are needed or not.

But the long strategic stalemate will not be destabilised by some flashy gadget like hypersonic missiles. As long as no effective defence is available against mass attacks with nuclear-armed missiles, mutual deterrence will persist. The only technological development that could really undermine it is directed-energy weapons.

High-energy lasers and particle beam weapons would be far more effective than the groundlaunched missiles employed today. They would have absolutely flat trajectories – which allows precise targeting – and would be able to switch instantaneously from one target to the next.

Directed-energy weapons would make effective defence possible against any nuclear attack. But nobody has come up with such a weapon in forty-plus years of trying.

Until then, innovations like hypersonic missiles are just minor new wrinkles in an unchanging strategic scene.

Russia spent what is clearly a great deal of money to develop a snazzy but pointless weapon.