But America is not only polarised within. It faces a polarised Pacific. Relations with China have reached their post-normalisation nadir after Trump’s years in office, when Trump and Chinese President Xi Jinping propagated their strongman cults of personality in parallel.

With Trump’s departure, ironically, polarisation abroad could worsen — even as US President Joe Biden has hitched the success of his presidency to taming polarisation at home.

Republican hawkishness toward China during the Trump years was almost certainly tempered, at least on the margins, by the constraints of incumbency. A complete collapse in US–China relations risked making a massive mess on the Republicans’ watch. Now in opposition, the Republicans no longer have the responsibilities of power to hold them back.

However inadvertently, Biden’s fixation on internal unity could trap him in a downward spiral with China. In a time when Democrats and Republicans agree on virtually nothing, they are increasingly unanimous on the China threat. A shared enemy abroad can serve as a soothing balm for polarisation at home.

If Republican bellicosity towards China quickens, Biden might feel pressured to keep pace. First, to protect his flank from attacks of being ‘soft on China’ or being too permissive toward China’s deteriorating human rights record under Xi. Second, because it would give him at least one issue on which Democrats and Republicans can still come together.

The relentless global drum-beats of COVID-19 and climate change signal, loud and clear, that coordinated action among great powers like the United States and China is more vital than ever. Yet it feels more elusive than ever.

All the complexities of trans-Pacific politics are being flattened into an escalating US–China conflict. Just like polarisation within a country marginalises those who identify with neither pole, a polarised Pacific is one where the interests of even major players in Northeast and Southeast Asia get sidelined.

Even when an event too big to ignore occurs, like the recent coup in Myanmar, this flattening is apparent. Rather than appreciating shared US–China interests in Myanmar’s stability or the country’s historical complexities, the discourse quickly devolves into depicting a zero-sum conflict for influence.

To warn of a ‘new Cold War’ between the United States and China is actually to understate the risks. Deteriorating relations between the United States and Japan in the 1930s are a better parallel than US–Soviet relations in the 1950s. Then as now, a rising Asian power tested US hegemony and challenged its rules. Once again, both sides are handling the rivalry more poorly over time.

The Japan parallel outperforms the Soviet parallel for an even darker reason. The past four years are a reminder of the centrality of racism in the United States’ political development. As John Dower showed, World War II in the Pacific was also a race war. Polarisation is nastiest when it activates hateful emotions, and nothing unleashes hateful emotions like racism.

The more US–China relations polarise, the more Sinophobia will exhale its rancid fumes. The greatest immediate risk of US–China conflict is growing attacks on Asian-Americans and Asians on US soil.

World politics can also polarise as a global rivalry between democracies and dictatorships, with the United States and China leading each camp.

Besides being gratuitously antagonistic, this perspective exaggerates US capacity for global democratic leadership. American democracy’s current mission is not to lead, but to survive. The US experience is an endless battle to sustain and extend democracy, not democratic exceptionalism.

Nor is dictatorship China’s fixed destiny. We need not lose hope that, after Xi departs, the Chinese Communist Party might resolve its governance challenges and rejuvenate itself through strategic democratic reforms. This is what authoritarian parties in Taiwan and South Korea did in the 1980s.

Yet whenever world politics is portrayed as a grand moral struggle of a US-led democratic camp against a China-led bloc of dictators, it makes democracy more repellent to China’s people. Democracy is most appealing when expressed as a universalistic value and practice, not as a status marker to join an exclusive club.

The United States is rightly recommitting to its Asian alliances after four years of recoiling from them. But there are costs to casting these alliances as one club striving to defeat a rival club. It exacerbates polarisation in the short run and makes democratisation across Asia a goal even harder to achieve — including in China — in the long run.

Dan Slater is Professor of Political Science at the University of Michigan and Director of the Weiser Center for Emerging Democracies (WCED). He is also a non-resident fellow at the Carnegie Endowment for International Peace.