There can be no question about the importance of borders in motivating recent political upheavals in the United States and much of Europe. In case any reader needs reminding, candidate Donald Trump’s slogans were “America First” and “Make America Great Again;” Brexit supporters vowed to “Take Back Control;” for Marine Le Pen, “the aim of this program is first of all to give France its freedom back.” In early 2016, Wendy Rahn and Eric Oliver found that Trump’s supporters were more likely, than even enthusiasts for other Republican candidates such as Marco Rubio and John Kasich, to endorse strong nationalist views. Later that year, Thomas Edsall reported a survey by Adam Bonica, finding that almost nine in ten Trump supporters agreed that “people living in the U.S. should follow American customs and learn English,” and that virtually all concurred that “patriotism and protecting our national identity is important.” Only a quarter of Clinton’s supporters shared the first view, and just over half the second.

That starting point leads me to wonder how deep the support is for Trump, Brexit, Le Pen, or hard nationalism more generally. After all, it is fairly costless and can be highly gratifying to express passionate support for one’s country in a poll or voting booth– but how many people are prepared to sacrifice some other value or interest for the sake of ardent nationalism, and under what circumstances? The answer is obviously “many” in a time of war or existential threat. But western Europe and the United States are, more or less, at peace and unthreatened, at least in comparison with German aggression of 1940, the USSR’s erection of the Berlin Wall in 1961, or the traumatizing terrorist attacks of September 11, 2001.  So what are Americans, Britons, or the French now prepared to do in the name of national sovereignty?  Will they accept higher prices for foreign-made goods newly subject to import taxes, or the loss of construction and domestic workers through more stringent immigration controls?  More poignantly, will Americans, Britons, or the French relinquish moral commitments to multiculturalism, protection of refugees, or shared human worth?

Of course, we do not know. The votes for Trump and Brexit are an uncertain indicator of support for hard-edged nationalism, in both directions. On the one hand, in an exit poll of 25,000 American voters on November 8, 2016, a third of those endorsing legalization of undocumented immigrants, nonetheless voted for Trump. On the other hand, 15 percent of voters who endorsed his plan to build a wall along the full border with Mexico voted against him, as did over a third of voters who agreed that international trade takes away U.S. jobs. A poll in February 2017 of “more than 44,000 readers of [Daily] Mirror websites” in the U.K. found Britons to be moving in both directions with regard to Brexit. Almost 14 percent of people who voted to leave would now vote to remain if there were a second referendum, while almost 10 percent would move in the opposite direction in this hypothetical second vote. Although “this switch in votes would see an overall result of 51.2% to 48.8% in favour of remaining in the EU,” my focus here is more the level of volatility than the outcome of the putative second vote. We cannot assume that this poll is representative of the British population as a whole, but it does show that, just as some Trump voters were soft on American nationalism, so some Brexiteers are now soft on withdrawal from the EU.

The crucial question with regard to public opinion and support for nationalism seems to be “under what circumstances?” (Ira Katznelson says that is the crucial question for all of social science.) That is, how tightly entwined are hard-edged nationalist identities, racism or xenophobia against people who seem to be storming the borders, economic despair or anxiety about jobs disappearing because multinational corporations are sending them overseas, and amorphous but sharp hostility to elites who write blog posts like this one?  If nationalism, xenophobia, fear of falling, and populism are intimately linked in mutual causation, public support for literal and metaphorical border hardening is likely to grow. But if these four motivating sentiments can be disentangled – so that, for example, immigrants are not seen as the cause of joblessness, or protectionism is not seen as necessary for job growth – then levels of nationalism are potentially more malleable and the costs of nationalism more salient.

The task of the left, or of people like me who viscerally fear and dislike nationalism, however, is to go even further than merely disentangling border protection from the woes of inequality or elite snobbery. We need to make a full-throated, positive, argument on behalf of the shared gains of migration, free trade, Schengen-type mobility, cosmopolitanism.  We need simultaneously, of course, to back this argument with concrete results, ranging from actually redistributing the gains from trade rather than mouthing truisms about Pareto optimality, to avoiding the patronizing behavior too often accorded to “fly-over country” full of dog-whistle racists.  Only then may politicians be able to find a way, if not toward genuine cosmopolitanism, then at least away from a new, multi-sided, cold war.

Further Reading on E-International Relations

• Opinion – Brexit and Its Many Identities in the UK
• Brexit and the Fight against Terrorism in the United Kingdom
• Opinion – Brexit and the Continued Troubles in Northern Ireland
• Opinion – Nationalism and Trump’s Response to Covid-19
• The Days of May (Again): What Happens to Brexit Now?
• Opinion – The UK’s Complicated and Contradictory COVID-19 Moment