Keep in mind
Space is already militarized with major nations all having military satellites in orbit, and the US, China and Russia all having flown manned missions for their respective armed forces. Also, as mentioned previously, China's entire space program is tied to their military. They have no civilian "NASA" like the US.
Sad to say, but the entire "space is a military free zone shared by all humanity" is a ridiculous pipe dream detached from reality. We might as well say every nation in the world all agrees to stop all military R&D.