But the U.S. wasn't alone in its interest in developing hypersonic capabilities. "China was watching and learning, and at some point started investing in hypersonics," Boyd says. "Since 2015 it became evident that significant progress was being made that, at least in numbers of flight tests conducted, appeared to show China outpacing U.S. efforts. And, in Russia, where they have worked on hypersonics for decades like the U.S., they also seem to have had recent successes with flight tests."
Russia's Satan-2 intercontinental ballistic missile, which the Moscow Times reported in April 2019 was in the final testing stages, can be equipped with up to 24 smaller, warhead-carrying hypersonic vehicles that it would release in an attack.
In response to the Chinese and Russian progress, the Trump Administration is pushing to develop hypersonic weapons as soon as possible, and is requesting funding of $2.6 billion for hypersonic research by the Air Force, Navy, Army and DARPA in its FY20 budget request. R. Jeffrey Smith, managing editor for national security for the Center for Public Integrity, reported in the New York Times Magazine that spending on developing hypersonic weapons could rise to $5 billion a year, as the U.S. pushes to develop a deployable hypersonic missile system in the next two to three years.
Though hypersonic missiles could carry nuclear warheads, the missiles being developed by the U.S. will only be equipped with conventional explosives. But they'll still be plenty fearsome. As Smith wrote in the Times, "the missiles function like nearly invisible power drills that smash holes in their targets, to catastrophic effect." They'll impact their targets with a force equivalent to three to four tons (2.72 to 3.63 metric tons) of TNT, according to Smith.
In some ways, hypersonic missiles present a different, perhaps even scarier threat to peace than present nuclear arsenals, because they could enable a nation to launch a surprise attack and cripple an enemy's ability to retaliate, leaving it helpless against the threat of a nuclear attack.
"There are several destabilizing effects," Boyd explains. "First, they are difficult to defend against because of their speed, and because they operate in a region between regular aviation and space which we are not used to defending, and because they are maneuverable which means they must be tracked accurately throughout their flight. Second, this class of missiles is not covered by any currently valid weapons treaty. This poses a number of concerns including the fact that the nations primarily involved (the U.S., China, and Russia) do not have established protocols in place for the use of these systems.Third, Russia has said that it is developing a hypersonic weapon that can deliver either a conventional or a nuclear warhead. This is particularly destabilizing because if such a weapon is launched, the nation under threat would not be able to determine whether a nuclear response must be considered."
"There are many ways to do countermeasures against missile defenses," Bruce MacDonald, an arms control expert and an adjunct professor at Johns Hopkins University's School of Advanced International Studies, explains via email. "Hypersonics is an expensive, technically more risky way to do so." But even so, "in a conventional conflict, an accurate very fast missile could destroy high value targets like missile silos or communication nodes before they could be launched or defended against. Plus decision making time for the attacked party is seriously compressed, giving leaders less time to make crucial high consequence decisions."
That all means that in the near future, hypersonic missiles could lead to a continuous atmosphere of hyper-anxiety, in which nations might be afraid not to strike first – or to instantly launch a counterattack – at the first hint of trouble. And that would be a world in which it would be too easy to make a catastrophically lethal mistake.
