Vietnam’s most senior leader, Nguyen Phu Trong, is to visit Beijing this week, just days before Donald Trump is sworn in as US president.
With China and the rest of the region braced for a diplomatic and economic storm following the inauguration of the erratic billionaire, Vietnam announced that Mr Trong would leave for China on Thursday.
It will be the communist party general-secretary’s first visit to Beijing in nearly two years, and the first since his surprise reappointment as party boss last year.
Vietnamese media said that the visit was aimed at developing healthy and stable relations between the two countries. The likely impact on the region of the Trump administration is sure to weight heavily on both leaders as they sit down to talk.
A series of aggressive statements from Mr Trump during and after the election campaign have indicated that China is firmly in his sights, as he seeks to enhance America’s global power and protect American jobs.
One early option is for Mr Trump to label China a currency manipulator.
Analysts fear that an aggressive Chinese response to such a move could quickly spiral into a trade war between the world’s largest economies.
Vietnam can take little comfort from heightened tension between the two superpowers.
Conflict between the two, particularly in the South China Sea, would leave Vietnam extremely vulnerable.
Mr Trump’s unpredictable statements and emotional responses to perceived threats makes the US an unreliable partner for Vietnam, as it seeks to balance the growing might of China.
Analysts suspect that Mr Trong may be urgently seeking a new accommodation with China over the two countries’ conflicting territorial claims in the South China Sea.
High level visits have continued between the two neighbours, with increasing frequency in recent months, as Vietnam seeks to defuse the offshore confrontation.
Mr Trump’s recent raising of the Taiwan card has threatened an even more combustible crisis.
If the new president follows up on his earlier phone call with the Taiwanese president, Tsai Ing-wen, and moves towards some degree of official recognition for Taiwan, the consequences could be explosive.
Mutual agreement on the “One China Policy” has been the essential underpinning of the relationship between China and the United States since the two sides sought reconciliation in the 1970s.
China has left observers in no doubt that it will consider a military option against Taiwan if the US gives recognition to Taipei.
Mr Trump’s response to the North Korea challenge remains another source of deep unease.
With the future of the global liberal trading system potentially at stake, and even peace in Asia looking fragile, Vietnam has much to lose.
Nguyen Phu Trong and the other Vietnamese leaders have shown themselves to be extremely cautious diplomats, painstakingly knitting together economic and strategic partnerships with countries far and wide, and treading a delicate path between China and the United States.
The arrival of the Trump presidency blows any remaining certainties out of the water. Vietnam’s delicate diplomatic touch may finally have met its match.