It also goes beyond the US to its Western allies.
Australia has conducted its own joint exercises with China and is discussing more. European states are stepping up their own links and visits, and NATO is considering much closer liaison, perhaps over areas such as peacekeeping in Africa.
While some Western officials complain that Chinese warships operating alongside international forces in anti-piracy patrols off Somalia have spent at least as much time spying on foreign warships as hunting pirates, their presence there is broadly welcomed.
More informal links are increasingly embraced. Retired Western officers in particular are setting up loose networks and visits, sometimes taking along serving personnel.
Communication is helped by the increasing value the Chinese military puts on Western experience and English language skills. Zhang Zheng (張崢), the commander of China’s first aircraft carrier, speaks perfect English and studied at Britain’s Joint Command and Staff College.
Officers and diplomats say Chinese officials are more willing to share personal e-mail addresses and indulge in private conversations in ways unthinkable only a decade ago.
“We have more tools for contact and cooperation than ever before,” said Air Vice Marshal Michael Harwood, British defense attache to Washington until last year. “If I was advising a young officer today, I would tell him or her to learn as much about Chinese culture and make as many contacts there as they can.”
None of this, though, has diminished military tensions on some major points of disagreement.
US officials say they believe China is preparing a missile test to build its capability to knock down US satellites and last year, a series of maritime border disputes brought friction between China and US allies, such as Japan and the Philippines.
The most persistent bone of contention, however, is cybersecurity.
The Pentagon earlier this month charged China with widespread espionage to acquire technology to fuel its military modernization, accusing Beijing for the first time of trying to break into US defense computer networks.
China issued a firm denial.
Espionage is a major concern for the West. Before allowing Chinese personnel access to any facility in the recent exchanges, the US and others generally conduct a “risk assessment” and security experts will often sweep afterwards for bugs.
Foreign powers are also wary of giving Chinese officers too much access to their training schools and military colleges, complaining Beijing almost never reciprocates by allowing Western nations access to its elite establishments.
While US law specifically prohibits providing China some forms of direct military training, European nations have fewer restrictions and, some officials say, must be careful.
“We don’t want to be training China in carrier strike [operations],” said one Western official said on condition of anonymity. “I think we can agree on that.”
Foreign experts say some elements of the PLA, having pulled out of many of their industrial interests in the last decade, have found stealing and selling intellectual property to be a lucrative earner.