The development of hypersonic missile-delivery systems by China, Russia and the USA has raised concerns as to what warhead the high-speed, long-range delivery system would use, plus how regulations surrounding their use would manifest.

All three nations have hypersonic missile systems that they are in the process of developing, but “there are benefits and risks of boost glide technology”, James Acton, co-director of nuclear policy programmes at Carnegie Endowment for International Peace, has told the EU’s Non-Proliferation Consortium conference in Brussels.

China reportedly tested a system in 2014, while the USA has its Advanced Hypersonic Weapon and Conventional Prompt Global Strike programmes under way. The latter of these aims to develop a capability that can deploy a missile anywhere in the world within one hour.

“The big potential difference between Russia and China, and the US is that Russia and China may be interested in delivering nuclear weapons,” Acton said.

There are “very complex risks” involved with this, he says, and there is no credible way of distinguishing between a boost glide weapon and a guided ballistic missile.

“For example, a ballistic missile is entirely predictable: when it’s launched, you know exactly where it’s going to land,” he said. “A boost-glide weapon is not predictable because it can manoeuvre mid-course. That creates the possibility that a weapon fired at, say, North Korea, could be misinterpreted by China that it is heading towards China. Or a weapon fired at Iran could be interpreted as heading towards Russia. This is destination ambiguity.”

However, he says there is nothing that can be done to stop development in this area, because it would effectively rule out the use of systems that are currently in operation.

“Prohibiting that entire class of weapons… would require banning weapons that already exist, and I think that’s a non-starter,” he said.

On the other hand, it may require the development of politically guided agreements that would enforce regulations, such as sharing launch notifications among states that deploy these technologies. Making nations treaty-accountable also could ensure that the warhead is conventional, not nuclear.

The reason behind the development is also questionable, with technology driving the creation of hypersonic weapons.

“This is driven by technology… and technologists think that once it is built they will work out what to do with it,” Acton said. “That is not to say that these things won’t be useful – that remains to be seen – but it is to say that they have been driven by technology today, not by strategy.”

The Pentagon has floated ideas on what it might want to use them for, including denying a new proliferator the ability to use nuclear, biological or chemical weapons – which is aimed at North Korea and possibly Iran – and for attacking anti-satellite capabilities, which is potentially aimed at China.

Other targets would be attacking anti-access, anti-denial areas that stop US forces moving around a theatre of operations, which is again largely aimed at China, as well as using them for anti-terrorism tasks.

“I think the chances of a huge number of countries starting boost glide weapons programmes tomorrow is pretty slim, but within the next decade is fairly likely,” Acton added.