When John F Kennedy became US president in January 1961, he was determined to meet his Soviet counterpart, Nikita Khrushchev, directly. It was better, he told advisers, "to meet at the summit rather than the brink".
Last week's meeting between Chinese President Xi Jinping and US counterpart Joe Biden in California suggests both sides, at least in part, hold a similar view.
The meeting produced a range of agreements and talking points, including resuming military-to-military communications and China reportedly agreeing to crack down on production and export of the synthetic drug fentanyl, responsible for a major crisis within the United States.
But on Taiwan, arguably the most important single point for US-China relations and also the most likely to spark a war, there was little direct progress, perhaps even a warning.
It marked the latest stage in a high-stakes dance between Washington and Beijing over the self-ruled island that China claims as its own, intensifying steadily throughout the 2020s.
US officials have briefed that they believe China is working to be ready to invade Taiwan by 2027 -- some believe sooner -- even at the risk of triggering a wider war. According to US officials at the meeting, Mr Xi denied that such plans existed -- but accompanied that with comments that suggested use of force was perhaps increasingly on the table.
"Reunification" with Taiwan, Mr Xi told Mr Biden, was unstoppable. The US, he said, must ensure Taiwan did not declare independence, and instead push the Taipei government towards "peaceful reunification", including through ceasing supplies of US arms shipments to the island.
According to a US official with knowledge of the meeting who briefed reporters immediately afterwards, Mr Biden repeated what has been US government policy for decades -- that the current status quo should be maintained.
According to the same US official, Mr Xi warned that was now untenable, stating: "Look, peace is all well and good, but at some point we need to move towards resolution more generally."
That unsurprisingly has unsettled some. Chinese officials once talked in terms of the 2049 centenary of Communist victory in the Chinese Civil War as their target date for unification, but Mr Xi's comments appeared to suggest a shorter timeframe.
While most Chinese commentary praised the meeting as productive, some hawkish voices talked of the importance of the United States, Taiwan's biggest arms supplier, keeping its "promises", in some cases implying that Mr Biden had agreed to halt weapons shipments.
That was rejected immediately by US Defense Secretary Lloyd Austin, who said nothing would change in terms of Washington's support. Taiwan is currently awaiting the arrival of a delayed delivery of US-made F-16 fighters.
China's former ambassador to Washington, Cui Tiankai, told the South China Morning Post last week that China now saw the Taiwan question as "life-and-death for all Chinese", with "no room for concessions" and a necessity to be "prepared to do anything to defend our national sovereignty".
In the next breath, however, he said Beijing would continue to seek reunification by peaceful means and that as long as the "one China" principle was respected, "everything is negotiable" despite "limits" on how much Beijing could be provoked.
'COMPLICATED' MOMENT
Overall, the Biden-Xi meeting, which took place alongside the Asia Pacific Economic Cooperation forum in California, suggested both sides were at least happy to be talking.
Mr Xi appeared genial and relaxed, and there was a clear desire to find multiple areas of common ground, a significant improvement on last year's meeting on the sidelines of the Bali G20.
But what that really means is hard to say. As Japanese leader Fumio Kishida put it after his own meeting with Mr Xi, "the international community is at a historic turning point where growing confrontation and cooperation are woven in a complicated manner".
Certainly, as soon as the Apec gathering concluded, Taiwanese officials reported renewed posturing by Chinese forces in the Taiwan Strait, the strip of water that divides the island from China.
January will see elections in Taiwan, likely to be won by the ruling Democratic People's Party, which paints them as critical to the island retaining its democracy and civil freedoms.
The previously nationalist opposition Kuomintang has increasingly favoured closer contacts with the mainland but has struggled to win votes as China ramps up military tensions.
Combining threats with relationship-building at major diplomatic meetings is not as unusual as it sounds. Kennedy's first meeting with Khrushchev in Vienna in June 1961 saw the US delegation shocked by the aggression of the Kremlin leader as he threatened to overrun West Berlin and its US, French and British defenders. Having hoped to improve relations, Kennedy instead found himself warning such Soviet action would prompt an immediate worldwide war.
The USSR did not attempt to overrun Berlin. But within months, it sparked a new crisis with the building of the Berlin Wall, followed by the deployment of Soviet atomic rockets in Cuba in 1962.
MORE BRINKMANSHIP TO COME?
The lessons of that for the modern era are concerning. Only after the US and Soviet Union had come to the very edge of catastrophe in Cuba did truly meaningful communications start, including the creation of a hotline between the Kremlin and the White House.
Mr Biden and Mr Xi agreed to set up a similar communications line last week -- but it is far from clear that either side is close enough to the brink for a similar commitment to de-escalate.
That doesn't mean these meetings are a waste. In the face of the Cuban missile crisis, the fact Kennedy and Khrushchev had met each other arguably helped the diplomatic process of detente that began immediately after, reducing the nuclear danger for almost two decades.
Declassified documents suggest another "war scare" in 1983 added further impetus to East-West negotiations, reducing tension once again as the Cold War approached its end.
A few years ago, the consensus would have been that Beijing had too much to lose by launching an invasion of Taiwan, not just because of the possibility of a US military response but also because of the interconnectedness between the world's two largest economies. But Chinese trade with the United States is falling steadily each month, as are wider Chinese exports, undercutting economic growth.
Invading Taiwan would still be a colossal gamble for China, the world and Mr Xi himself. Khrushchev lost his grip on the Kremlin in the aftermath of the Cuban crisis in 1962, replaced by senior Soviet officials who felt he had taken far too great a risk.
The costly, messy examples of the 2003 US invasion of Iraq and 2022 Russian invasion of Ukraine might also give him pause.
For now, the most likely scenario is that Mr Xi and those around him have not yet decided what to do, looking to keep their options open while using meetings like that in California to gauge the strength of their position.
These summits are important, but the real meat of this drama is likely yet to come. Reuters
Peter Apps is a Reuters columnist writing on defence and security issues. His first book -- 'Deterring Armageddon: A Biography of Nato' -- will be published in February.