With China, Russia, and the United States fine-tuning anti-satellite (ASAT) warfare capabilities, the third round of competition to “seize the high ground” of space is well underway. This round is distinctive, because it has three contestants, whereas the first and second rounds, which occurred during the Cold War, had only two. But, like its predecessors, today’s space race poses the risks of quick escalation and intensification of conflict among major powers. A set of common-sense rules could help defuse and prevent conflict in space. Unfortunately, Russia and China seem uninterested in negotiating a code of conduct for responsible space-faring countries.

The first space race began in 1957, when the Soviet Union launched Sputnik, the first artificial Earth satellite. US President Dwight Eisenhower’s administration opted to leave Sputnik and its successors alone, recognizing that the US could outpace Soviet space programs and had more to gain from not destroying them.

Eisenhower’s successor, John F. Kennedy, arrived at the same conclusion. But he went a step further, joining with the Soviet Union to champion a United Nations resolution on cooperation in space. Kennedy’s eyes had been opened by a July 1962 US atmospheric nuclear test that inadvertently destroyed at least six satellites, including some belonging to the USSR. A few months later, the Cuban missile crisis spurred agreement on a ban on atmospheric testing. In 1967, US President Lyndon Johnson and Soviet leader Leonid Brezhnev turned UN resolutions into the Outer Space Treaty, which marked the end of the first military space competition.

The second round of competition emerged in the mid-1970s. Brezhnev’s Soviet Union tested a new type of ASAT weapon, and President Gerald Ford’s administration decided to respond in kind. Under President Jimmy Carter, the US tried diplomacy to limit ASAT programs, but the superpowers couldn’t begin to agree on how to define a space weapon.

Then, in 1983, President Ronald Reagan’s administration launched its Strategic Defense Initiative, which ratcheted up the competition. The second wave of competition ebbed in 1987, when Reagan and Mikhail Gorbachev agreed to a treaty eliminating intermediate-range missiles, and ended when the Soviet Union dissolved.

The latest round of military competition in space began in 2001, when the US, under President George W. Bush, withdrew from the Anti-Ballistic Missile Treaty and demonstrated advanced space-enabled military targeting in its war in Iraq. At that time, Russia was in no position to compete. But the Kremlin gradually boosted investment in “counter-space” capabilities. China did the same, demonstrating a new “hit-to-kill” ASAT weapon system in 2007. China’s test, like the US atmospheric nuclear test in 1962, was highly damaging to the space environment, creating a vast, indiscriminate, and lethal debris field.

In 2008, the US used a specially adapted sea-based interceptor missile to shoot down a malfunctioning US intelligence satellite just before its reentry into the atmosphere. The US now uses an unmanned miniature version of the space shuttle to practice “proximity operations”: approaching other satellites without harming them. Russia has launched three satellites for proximity operations. Chinese ASAT tests have succeeded to the point that they are now designed to miss their targets.

The third round of military competition in space remains less intense than the first two, but it is gathering momentum. The question is how to defuse it.

Russia and China support an international treaty to prevent the weaponization of space. But their proposal has significant drawbacks, including the same old difficulty of agreeing on what constitutes a space weapon. Most space-related capabilities, like lasers and proximity operations, have both peaceful and military applications. Monitoring and verifying compliance is another challenge. And even if provisions could be agreed, ratifying and implementing a treaty could take decades, as with the Comprehensive Nuclear-Test-Ban Treaty.

A simpler – though by no means easy – approach would be to agree on a code of conduct for space. The good news is that the framework for such an international code – conceptualized by the Stimson Center (which I co-founded) in 2002 – already exists, drafted in detail by the European Union. The bad news is that China and Russia, along with many developing countries, have voiced strong objections.

Developing countries disapprove of the EU’s attempt to avoid a UN-based drafting process. And they have balked at the draft code’s affirmation of a national and collective right to self-defense – a right enshrined in the UN Charter. China and Russia would like to limit the code to civilian and commercial space activities – even though military space programs are the crux of the problem and the main impetus for developing a code in the first place. The draft treaty supported by Russia and China would constrain only weapons in space, not their ground-based ASAT programs.

Russia and China are clearly not ready to curtail their ASAT capabilities; and the US is ramping up its own. Transparency and confidence-building measures can help. So can guidelines for the sustainable use of outer space, which may emerge from the UN’s Committee on the Peaceful Uses of Outer Space. But the third round of space competition will not end until all major powers are ready to endorse a code of conduct for responsible behavior.