Die empty has already hit the nail on the head, this is not a direct attack on cryptocurrency for now, but they are considering the risk at stake in having a Chinese based crypto mining facility near their own sensitive military coverage,
The USA and China has never seen each other eye to eye. They are both known as very powerful nations who are on the opposite sides.
I am pretty sure even if it wasn’t crypto-related, the US government could still have been more cautious and suspicious of their position. This whole ordeal might not help cryptocurrencies grow as cryptocurrency might serve as a reason or cause for US’s suspicions specifically on China.