It is interesting to see how, in one month, Mars suddenly had three visitors from Earth. First, the United Arab Emirates’ probe named Amal, or Hope, arrived on February 9; a day later, China’s Tianwen-I entered Mars’ orbit. Perseverance, Nasa’s newest rover, landed on the red planet’s surface on February 18. Why can’t nations pool their resources and knowledge on such gargantuan tasks that are extremely difficult and expensive?

In outer space, all issues basically boil down to two categories: peaceful use and demilitarisation of space. No matter how desirable the former sounds, the latter is the real challenge. US Secretary of Defence Lloyd Austin described space as “an arena of great power competition”.

But, during the Cold War, the United States and Soviet Union managed to cooperate on the Apollo-Soyuz Test Project, the first international partnership in space. On July 17, 1975, an American Apollo spacecraft, launched two days earlier, docked with a Soviet Soyuz spacecraft.

Sadly, this won’t happen between China and the US, the two largest economies today. The Wolf Amendment limits US government agencies such as Nasa from working with Chinese commercial or governmental agencies. However, a prosperous China can afford to invest lavishly in a domestic space industry that is self-propelled and sustainable.

In some areas, China has already overtaken the United States. China’s 500-metre Aperture Spherical Telescope, larger than the US-run Arecibo spherical reflector dish in Puerto Rico, is the biggest in the world. On December 1, 2020, the same day a Chinese lunar probe landed on the moon, the Arecibo dish collapsed.

Unlike Washington, which does not allow Chinese astronauts into the US-built International Space Station, Beijing appears more open-minded about space cooperation with other nations.

Beijing has said it is ready to share its moon samples with international institutions and scientists as space belongs to everyone. It has also declared in a UN memorandum that China’s space station, set to be completed in 2022, will be used for international scientific experiments and flights for international astronauts.

The International Space Station is scheduled to expire in 2024. But even after a life extension to 2030, which passed in the US Senate but has stalled in the House of Representatives, China’s space station might be the only one in orbit. Will the Americans ask Beijing for a ride then?

Avoiding militarisation of outer space, however lofty the aim, is easier said than done. The 1967 Outer Space Treaty prohibits placing any weapons of mass destruction in orbit, establishing military bases or installations, testing any type of weapons or conducting military exercises on the moon and other celestial bodies.

Since the 1980s, the UN has had several debates on avoiding a space arms race. So far, though, countries have failed to negotiate another treaty for the purpose. In 2018, the US voted “no” on four UN resolutions which included prevention of an arms race in outer space and no first placement of weapons in outer space.

One outstanding problem is how to define what constitutes a space weapon or the weaponisation of space. Most space technologies are dual-use in nature – the same technology can be used for military or civilian purposes. Even a satellite that can move close enough to another satellite can pose a threat. Lasers, electronic jamming, directed energy weapons and offensive cyber tools can all become weapons that threaten satellites.

A difference in interpretations should not be an insurmountable barrier if all countries agree there will be no winners in a space arms race. The US, China, Russia and India have successfully conducted anti-satellite tests. The US is more vulnerable than any other countries because it has more civilian and military assets in space that are subject to potential attacks from adversaries.

Beijing is vulnerable, too. In the past three years, China had more rocket launches than any other country. Space is becoming increasingly crowded. In a single launch in January, a SpaceX Falcon 9 sent 143 small satellites into orbit, and thousands of new satellites will be sent to orbit in the coming decade. Every nation has a stake in space security.

The lessons of the Cold War might prove useful. During that time, mutually assured destruction helped prevent an all-out nuclear war. This concept only came into being when Washington and Moscow decided they could not have an edge over the other in the arms race and a strategic equilibrium, even balanced by terror, was more desirable than war.

Similarly, in avoiding militarisation or weaponisation in space, perhaps the way out is recognition of mutually assured vulnerability by major spacefaring nations that eventually leads to a treaty agreeing not to deploy any weapons in outer space.

If enemies could cooperate during the Cold War, why not competitors today? It is a relief that the Biden administration has renewed the New Start nuclear arms control agreement. The agreement prohibited, among other things, either country from interfering with the other side’s “national technical means” for monitoring compliance. This is understood to include satellite reconnaissance systems.

China-US cooperation in selected civil space projects will steer more countries to join the effort to develop space. It is possible, too. During China’s 2019 moon exploration mission, Nasa got Congressional approval for a specific interaction with China’s National Space Administration to monitor China’s landing of a lunar probe on the dark side of the moon using Nasa’s Lunar Reconnaissance Orbiter.

Competition is part of human nature, but no human folly is more monumental than attempting to place weapons in orbit to strike Earth to eliminate adversaries. Astronaut Michael Collins once suggested that the political leaders of the world should see their planet from 160,000 km away to change their outlook. What could they see? “The all-important border would be invisible, that noisy argument suddenly silenced.”

Senior Colonel Zhou Bo (ret) is a senior fellow of the Centre for International Security and Strategy at Tsinghua University and a China Forum expert