c/space Rules
The Wolf Amendment was enacted in 2011 and prevents direct U.S.-Chinese bilateral cooperation except in cases where the FBI can certify that there is no national security risk to sharing information with the Chinese side in the course of work.
Read: "We want to steal more of your technology. In exchange, here's a moon rock."
Is the obstacle that we’re the only country on earth that already has our own moon rocks to study and they were gathered by human hands?
The obstacle is the US government forbidding any cooperation between NASA and China's space program. Thankfully acedemics in the US and China find ways to circumvent these rules in some cases.
But yeah, jealously guard your old moon rocks, I doubt you'll be getting any more.
Just you wait until they figure out how to stop their rockets from exploding on launch or leaking helium everywhere! You won’t be laughing then!
Why was NASA complaining about it then?