I think China has been preparing an attack on the US since the early 90’s at least. China tried to take ownership of the Panama Canal, at the same time one of the Navy bases in California was up for grabs and they wanted that. Then they bought a whole fleet of planes from Boeing (troop transports). Clinton gave then MIRV technology (multiple re-entry warheads).
Their generals openly make comments about how to defeat the US in a coming war.