Nationalism is one of modern Europe's strongest traditions, but it fell into disrepute after World War II. Amid the avalanche of crises that have struck the European Union over the past decade, of which Britain's vote to leave the bloc is the latest example, nationalism is making a reappearance.
It takes a different form from the nationalism born in the 1789 French Revolution and buried in 1945. Today's political and economic conditions are a world apart from those of 19th-century Europe, when many peoples rising to national consciousness had no state of their own. They are a world apart, too, from the 1918-1939 age of ideological extremes - fascism and communism - and severe economic hardship.
Contemporary Europe is, fundamentally, a peaceful and prosperous continent. The EU provides a framework for extremely close cooperation among national governments. It entrusts considerable power to supranational institutions such as the European Commission, the European Parliament and the European Court of Justice. At a popular level, too, European societies are better acquainted with one another than ever, thanks to advances in communications, education and the ease of mass travel.
Yet nationalism, in new guises, is back on the stage. Its most obvious manifestations are, firstly, a stronger determination on the part of governments to defend their national self-interest within the EU and, secondly, the rise of right-wing populist nativism.
Both developments reflect profound political and social trends. There is a general mistrust of political elites, partly in Brussels but mainly at the national level. More specifically, European voters of the moderate centre-left are losing faith in the capacity of 20th century-style social democracy to deliver economic security and protect identity.
The instinct to defend national self-interests in Brussels was never, of course, completely absent even in the heyday of EU integration in the 1980s and 1990s. However, it has soared to new heights amid the euro zone's struggles to hold itself together and last year's refugee and migrant emergency.
It is visible in the paralysed effort to deepen Europe's banking union by means of a common deposit insurance scheme. It is visible in the ceaseless search by some governments to find ways of bending legally enshrined rules on fiscal discipline. And it is visible in a commission decision last week to let national Parliaments have a veto over the terms of an EU-Canada trade deal. National self-defence is likely to torpedo a proposed EU-US trade accord, too.
A year ago, the EU's "five presidents" - of the commission, European Council (which groups national leaders), European Central Bank, euro zone finance ministers' group and Parliament - published a report on advancing economic, financial, fiscal and political union. Copies of the tepidly received report are gathering dust in the filing cabinets of national capitals.
No big push on integration is conceivable until after next year's French presidential election and Germany's parliamentary elections. Even then, it may not happen. France's centre-right opposition Republicans, who are well placed to win the presidential contest as well as the ensuing legislative elections, envisage stricter national border controls, a reduced role for the commission and more national influence over common EU policies. This stance has much in common with that of Poland's conservative nationalist government.
The second form of nationalism in today's Europe is radical right-wing populism. This is a more potent force than left-wing radicalism, as can be seen in the defeat of Podemos in Spain's elections last month, the increasing unpopularity of Greece's Syriza-led government and the blind alley into which Mr Jeremy Corbyn and his neo-Marxist allies are leading Britain's Labour Party.
The radical right, at least in Western Europe, is less anti-Semitic than it was during France's Dreyfus affair in the 1890s and under German Nazism. Rather, it is Islamophobic and anti-immigrant. In October, Austria will stage a re-run of its presidential election that may see a candidate of this type become the EU's first such democratically chosen head of state.
Yet the radical right is more than nativist. It draws on a well of angry attitudes among sections of society that are offended not only by multiculturalism, or by losing out in a globalised economy, but also by liberal values as such. Surveys of British voters in the June 23 referendum on EU membership show that one of the surest guides to whether someone would vote Leave was whether he supported a return to capital punishment.
Part of the appeal of right-wing populism is that it hammers away relentlessly on the theme that mainstream political parties, especially since the end of the Cold War, are almost indistinguishable from one another and offer no proper choice. Not without reason, the parties are depicted as corrupt and detached from everyday life. But far from everything is running in the populists' favour.
Their chief weakness is that they have no economic policies beyond an iconoclastic rage at the euro, free trade and foreigners alleged to be parasites on the welfare state. The new nationalism, in its radical rightist colours, has no credible solutions for a modern Europe that, despite all its troubles, must pin its hopes for a better future on mutual cooperation and an open face to the world.
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