And Russia, of course; American astronauts have been going up on Soyuz since the end of the Shuttle program.
If you're suggesting that the US could go to China for replacement transportation services: not likely. NASA is currently barred by Congress from any cooperation with the Chinese at all on space exploration. At least one of the US commercial crew competitors are likely to have working hardware long before that attitude changes.
If you're suggesting that the US could go to China for replacement transportation services: not likely. NASA is currently barred by Congress from any cooperation with the Chinese at all on space exploration. At least one of the US commercial crew competitors are likely to have working hardware long before that attitude changes.