US President Donald Trump’s suggestion that he might speak directly with Taiwan’s President Lai Ching-te about weapons sales matters not because a call has been scheduled – it has not – but because of what his language already signals. By discussing Taiwan’s defence in the context of his dealings with Chinese President Xi Jinping, Trump risks making US arms sales look like a tradable item in US–China bargaining. That is exactly the frame that Beijing wants.

Since Washington switched diplomatic recognition from Taipei to Beijing in 1979, there has been only one publicly documented direct conversation between a US president or president-elect and Taiwan’s sitting leader: Trump’s December 2016 phone call, as president-elect, with then president Tsai Ing-wen. There are no publicly documented face-to-face meetings and no other known phone calls between US presidents and Taiwanese leaders during that period. This reflects the unofficial nature of the United States’ relationship with Taiwan.

A Trump–Lai call would be more norm-shattering than even the 2016 call. Trump is now a sitting president. Trump has tied the possible call directly to a pending arms package reportedly worth up to US$14 billion (A$19 billion). And it follows a Trump–Xi summit at which Trump said Taiwan and arms sales were major topics of discussion. The possible Lai call would not just be a protocol shock but would sit inside a live negotiation over Taiwan’s security.

Legally, there is no obvious statutory bar on Trump speaking with Lai. The One-China policy of the US doesn’t prohibit high-level communication. Washington has steadily expanded contact with Taiwan in recent years, including through congressional visits, senior official interactions, transit arrangements and updated State Department guidelines.

But the real issue is not legality; it is signalling. The strongest argument for a Trump–Lai call is that it could reassure Taiwan when Trump himself has generated so much uncertainty. Lai would almost certainly use the call to stress Taiwan’s commitment to the cross-strait status quo and to argue that China, not Taiwan, is destabilising the region through coercion. A disciplined call could reinforce that US arms sales are about deterrence, not provocation; that Taiwan’s democracy deserves respect; and that Beijing doesn’t get a veto over every form of US–Taiwan communication.

There is also a reasonable case that Washington should not allow Beijing to define every symbol of the latter’s One-China policy. The US–Taiwan relationship has changed dramatically since 1979. Taiwan is now a consolidated democracy, an economy central to global technology systems, and a frontline target of Chinese military, cyber, diplomatic and political coercion. Treating its elected president as someone no US president can directly speak to looks increasingly artificial.

But that is the best-case version. It assumes preparation, discipline and strategic purpose. With Trump, those are not safe assumptions. The problem is that Trump has not framed the issue as a careful act of reassurance. He has framed Taiwan’s weapons sales as something to be weighed after discussions with Xi and potentially as leverage in a broader US–China bargain. That is dangerous. Under the Six Assurances – principles outlined by Ronald Reagan to guide US–Taiwan relations – the US position has long been that Washington did not agree to consult Beijing on arms sales to Taiwan. Under the Taiwan Relations Act, defensive arms are not a favour to Taipei or a bargaining chip with Beijing. They are part of the legal and strategic basis of US policy.

That is why a call with Lai could easily backfire. It could reassure Taiwan symbolically while undermining it strategically. If Trump speaks with Lai but then delays, reshapes or downgrades the arms package because of his discussions with Xi, the call will not demonstrate resolve. It would demonstrate Taiwan’s vulnerability to a more transactional US foreign policy.

Beijing would likely exploit that ambiguity. Its preferred narrative is that Taiwan is not a partner with agency but a card to be played by Washington and ultimately traded with Beijing. Trump’s language risks doing Beijing’s work for it. A direct call with Lai could look bold, but if it comes wrapped in the language of dealmaking, it may strengthen the perception that Taiwan’s security is negotiable.

A carefully prepared Trump–Lai call, explicitly tied to deterrence, supporting the status quo and approval of defensive arms sales, would be useful. It would reinforce that Washington does not let Beijing monopolise the channels of top-level political communication.

But an improvised Trump–Lai call linked to bargaining with Xi would be a bad thing. It risks blurring the line between reassurance and transaction, inviting Chinese retaliation, and deepening fears in Taipei that Trump sees Taiwan as a negotiating chip.

The issue is not whether Trump can speak to Lai. He can. The issue is whether he can do so in a way that strengthens deterrence rather than making Taiwan look tradable. Right now, that is the risk.

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