A fiery clash between Elon Musk and Donald Trump has put $22 billion in SpaceX government contracts—and key U.S. space missions—in jeopardy.

The conflict erupted after Musk criticized Trump’s tax and spending policies. Trump hit back with threats to cancel federal contracts with Musk’s companies. Musk responded by saying he would decommission SpaceX’s Dragon spacecraft, used by NASA to ferry astronauts to the ISS.

Although Musk later backed down, calling it “good advice” to cool off, his threat shook the space community. The Dragon capsule, backed by a $5 billion NASA deal, is currently the U.S.’s only crew-capable spacecraft.

The fallout raises serious concerns over the future of U.S. space operations and the stability of public-private partnerships in an increasingly politicized arena.