Flattery gets you everywhere with US President Donald Trump. But only while it lasts. Like any addiction, it needs regular boosts in higher doses.
Amid fierce bidding, Chinese President Xi Jinping won first prize as the most effective Trump flatterer last year. All it took was a lavish banquet in the Great Hall of the People. In return, Mr Trump forgot to raise America's trade complaints or human rights concerns. Mr Xi easily outflanked the United States at the Asian summits following Mr Trump's China visit. If the key to seducing him is a dish of kung pao chicken, what's not to like?
The problem is that Mr Xi must continually feed Mr Trump. At a certain point, the ratio of Trump flattery to loss of self-respect will be too high. Would another flurry of trademark approvals for Ms Ivanka Trump break China's bank? Probably not. What about giving the go-ahead for a Trump Tower in Shanghai? Possibly.
Another red carpet reception is unlikely to cut it. The law of diminishing returns applies to favours already bestowed. This year, it is likely to turn negative. China has always been in Mr Trump's sights. Massaging his ego buys only brief respite.
The other ego is Mr Xi himself. China has acted with caution for more than a generation. For Washington's "never Trumpers", Beijing's restraint gave it honorary membership of the axis of adults that would curb Mr Trump's instincts. If Mr Trump was a loose cannon, China could be counted on to behave responsibly.
In the opening months of Mr Trump's presidency, Mr Xi did just that. China, not the US, is now the darling of the Davos economic elites. Mr Xi can lecture on Ricardian trade theory with the best of them.
But China's age of forbearance is over. In October, Mr Xi opened a bolder chapter in China's foreign ambitions. Deng Xiaoping, China's great moderniser, spent his last years with no official role other than chairman of the China Bridge Association. Mr Hu Jintao, Mr Xi's predecessor, was happy with just being president. Mr Xi, by contrast, has grabbed every title going and immortalised his own thought in the party's Constitution. Mr Trump has competition, in other words.
For the first time since Mao Zedong, China has a living personality cult. US-China relations are now in the hands of two gargantuan egos.
That is bad news for this year. Added to this are two bigger clouds. For the first time since the Cold War, the US has an explicit competitor.
Mr Xi's China has set itself the target of becoming the world's top dog within a generation. Unlike the Soviet Union, China can sustain technological rivalry with the US. America's dominance in the Asia-Pacific is no longer a given. Mr Xi's aim is to achieve military parity.
Second, the American President thinks in hourly increments. China's leader plans in decades. The battle between these two egos is one-sided. Mr Xi holds a telescope. Mr Trump stares at the mirror.
The scope for misunderstanding is growing. Too much attention has been paid to the spectre of a nuclear conflict between the US and North Korea - too little to the looming fallout in US-China relations. That is despite Mr Trump's latest tweet boasting that he has a bigger nuclear button than Mr Kim Jong Un. The US President still believes China can disarm the North Korean leader on America's behalf. No one else thinks that is likely.
Last week, Mr Trump said his patience with China was running out. The US President's advisers have so far curbed his protectionist impulses. But Mr Trump is rarely muzzled for long. His one consistent belief is that the US is being ripped off.
China, whom he has repeatedly accused of raping America, tops the list. "If they don't help us with North Korea, then I do what I've always said I wanted to do," he told The New York Times. We should expect this year to produce US trade actions against China, and Beijing to fight them at the World Trade Organisation. There will also be more nuclear tweets.
But the US-China fog extends far beyond the Korean peninsula. As does the potential theatre of confusion.
Last year, China opened its first overseas base in Djibouti. A Chinese aircraft carrier made its first visit to the Mediterranean. Mr Xi also stepped up China's installations in the South China Sea - a subject on which Mr Trump has yet to comment.
Mr Trump has not uttered the word "Taiwan" since he spoke to its leader after his election. His first tweet of this year was to accuse Pakistan of "lies and deceit".
China rushed to Pakistan's defence. "China and Pakistan are all-weather partners," said Beijing after praising Islamabad's "outstanding contribution" to fighting terrorism.
Mr Trump was far closer to the truth. But there are few gulfs of perception wider than that.
In a stand-off between Mr Trump and Mr Xi, who would blink first? There is no way of knowing.
However, China is giving hints of overconfidence. From the Iraq war to Mr Trump's election, China has been reaping one windfall after another. His disdain for democratically elected leaders plays straight into Beijing's hands.
But its luck cannot last forever. Mr Xi should remember that Mr Trump launched missile attacks on Syria when the two were having dinner in Mar-a-Lago. Many in China believe Mr Trump is a paper tiger. They may be right, but it would be rash to test that theory.