Pesident Donald Trump has signed the National Defense Authorization Act for 2020 that establishes the creation of a Space Force as the sixth branch of the U.S. armed forces — despite the landmark The Outer Space Treaty of 1967, which designated space as a global commons to be used for peaceful purposes.

The treaty was put together by the United States, the former Soviet Union and Britain, and since been signed by most nations on Earth. Craig Eisendrath, as a U.S. State Department officer involved in its creation, has said that “we sought to de-weaponize space before it got weaponized…to keep war out of space.”

It prohibits the placement of weapons of mass destruction in space. Although the Trump administration and U.S. military have said a Space Force is necessary because of Russia and China moving into space militarily, Russia, China and Canada have lead for decades in pushing for an expansion of the treaty. They’ve advocated for the UN’s Prevention of an Arms Race in Outer Space resolution, which would affirm a ban on placing weapons in space. The United States has opposed the PAROS treaty and has effectively vetoed it at the UN.

At the defense authorization act signing Dec. 20, Trump said forming a Space Force marked “a big moment.” He said: “Space. Going to be a lot of things happening in space. Because space is the world’s newest warfighting domain.”

Trump’s advocacy of a Space Force “started as a joke,” as National Public Radio has reported. NPR’s Claudia Grisales related that in March 2018 “Trump riffed on an idea he called ‘Space Force’ before a crowd of Marines in San Diego. It drew laughs.” Subsequently, Trump noted: “I said maybe we need a new force, we’ll call it the Space Force. And I was not really serious. Then I said, ‘What a great idea, maybe we’ll have to do that.’”

I’ve investigated the possibility of space becoming an arena of war since President Ronald Reagan’s “Star Wars” scheme of the 1980s.

This has included writing a book, “Weapons in Space,” and writing and narrating three TV documentaries. I’ve been to Russia several times, and I’ve been to China. What these nations want is the PAROS initiative and not to waste their national treasuries on weapons in space.

I recall sitting with Chinese diplomats after I spoke at a UN a conference on the threat of weaponization of space. They stressed how they need to feed, educate, house and provide health care to their people. My speech was followed by the Chinese UN ambassador speaking about how his nation sought to keep space for peace.

But if the United States moves ahead with a Space Force, China and Russia, and then other countries, will respond in kind. China and Russia won’t accept “American dominance” of space, and there would be an arms race in space.

The Global Network Against Weapons & Nuclear Power in Space held a protest against space weaponization in Florida at which Apollo astronaut Edgar Mitchell participated. He said, “any war in space would be the one and only.”

Bruce Gagnon, coordinator of the Maine-based Global Network, said Mitchell warned at the protest that in the event of war “activity on Earth below would immediately shut down — cell phones, ATM machines, cable TV, traffic lights, weather prediction and more — all hooked up to satellites, would be lost. Modern society would go dark.”

China has said that a U.S. Space Force would be a “direct threat” to peace. Its foreign ministry recently said the world should “adopt a cautious and responsible attitude to prevent outer space from beginning a new battlefield and work together to maintain lasting peace and tranquility in outer space.”

War in space would be calamitous.

Karl Grossman is a professor of journalism at the SUNY College at Old Westbury. He is author of “Weapons in Space” and writer and narrator of the TV documentary “Nukes in Space: The Nuclearization and Weaponization of the Heavens.”