What's China up to with North Korea?

Donald Trump said President Xi Zinping was the best poker player in the world. By that he meant you never know what the Chinese leader has in his hands or in his brain or up his sleeve!! Enigmatic and inscrutable are words coined for men like President Xi. So what is he up to right now over the North Korea issue? Clearly he is pulling all the strings attached to Kim Jong-un in the preparations for the summit between him and Trump, or at least the proposed summit. But what don't we know? The answer is we know nothing because everythng is being handled in great secrecy behind the scenes and we can only guess. But I think the Pentagon and the CIA and the massive power of the National Security Agency (NSA) have a pretty good idea what the devious Chinese president is engaged in. The Pentagon, out of the blue, has revoked the invitation it made to the Chinese Navy to join the US Navy and others in an international maritime exercise in the Pacific. China has already taken part twice in these naval exercises. It's all part of relationship-building to improve coordination between the Chinese military and the US military. But suddenly the Pentagon has decided to ban the Chinese navy from taking part. The official reason is that the US is angry over China's continuing militarisation of the sovereignty-disputed Spratly islands in the South China Sea, and in particular the deployment of surface-to-air and surface-to-surface missiles on these atols and the landing, for the first time, of a Chinese bomber on a runway constructed on one of the islands. Well these are good reasons for rescinding the naval exercise invitation. But the timing is significant. We are 20 days away from the planned summit in Singapore between Trump and Kim. This gesture of anger and defiance by the Pentagon is surely also aimed at Beijing for whatever Xi is plotting against the US in connection with the Trump/Kim extravangaza. There is more trouble ahead between now and June 12 and Beijing will be the cause of it. So it would look totally weird for Chinese and American sailors to be carrying out friendly naval duties together in the 2018 Rim of the Pacifc exercise while the Boss in Beijing is carrying on building up bases on these South China Sea islands and setting the agenda for a potentially disastrous summit between Trump and Kim next month. I don't suppose Beijing will worry very much about the cancellation of the naval exercise but Xi and his cohorts might just think: "Hm, what do the Pentagon and the CIA and the NSA know about our plots with Kim Jong-un? Have their spies and intelligence-gathering satellites picked something up which will undermine our plans?" I sincerely hope the Americans have managed to glean some vital intelligence. If they haven't, the inscrutable Xi and his prodigy, Kim Jong-un, will hold all the cards at the Singapore summit.