War exists now in many more dimensions than in previous centuries including non-conventional weapons and cyber, in addition to public sentiment, economic, social, political and military.

Considering the CIA's loss of double-agents, I'd say China maybe winning the HUMINT arms race at the moment.

There's too much to lose with direct military engagement (nuclear MAD), so competition will be limited to proxy wars, "sharp-elbow" island capture and overflights, trade wars and cyber attacks. The question becomes at what point does hard proof of attacks in these other domains necessitate an escalation of limited hostilities in the conventional dimensions (ie military).