By suppressing debate about Islam, nationalism and terror, the left set the stage for today’s backlash.

Donald Trump’s proposed border fence and his order to suspend all immigration from terror-producing countries are dramatic and consequential. But they’re also palliative symbols. The message: Your days of anxiety are behind you. We will be a coherent nation once more. Politicians across the West are saying the same thing in what is shaping up to be the widest rollback of the freedom of movement in decades. It’s not just right-wing nationalists like Marine Le Pen in France or Hungary’s Viktor Orbán. Centrists get it, too. Some, like Angela Merkel, are still-reluctant restrictionists. Others, like Theresa May, Dutch Prime Minister Mark Rutte and French presidential aspirant François Fillon, are more forthright. All have wised up to the popular demand for drastically lower immigration rates. The irony is that freedom of movement is unraveling because liberals won central debates—about Islamism, social cohesion and nationalism. Rather than give any ground, they accused opponents of being phobic and reactionary. Now liberals are reaping the rewards of those underhanded victories. Liberals refused to acknowledge the link between Islamist ideology and terrorism. For eight years under President Obama, the U.S. government refused even to say “Islamism,” claiming ludicrously that U.S. service members were going to war against “violent extremism.” Voters could read and hear about jihadists offering up their actions to Allah before opening automatic fire on shoppers and blasphemous cartoonists. Mr. Obama’s linguistic exertions didn’t repress the truth. They merely opened the space for others to express it—and sometimes to grossly distort it, by suggesting, for example, that all 1.4 billion Muslims are terrorists or sympathizers and should be kept out. The left also largely “won” the debate over Muslim integration. For too many liberals, every Islamist atrocity was cause to fret about an “Islamophobic” backlash. When a jihadist would go boom somewhere, pre-emptive hashtags expressing solidarity with threatened Muslims were never far behind. But liberals don’t bother nearly as much about the pathologies in Muslim communities, and in Islamic civilization itself, that were producing so much carnage. Some would sooner abandon their own feminist and gay-rights orthodoxies than criticize what imams in Paris and London suburbs were telling their congregations. Amnesty International cozied up to the British-Pakistani radical Islamist Moazzam Begg despite his fawning interviews with the al Qaeda preacher Anwar al-Awlaki. When Amnesty staffer Gita Sahgal went public with her objections in 2010, the organization suspended her and argued in a press release that “jihad in self-defense” wasn’t “antithetical to human rights.” The Islamist philosopher Tariq Ramadan became the toast of New York intellectuals, though he refused to call for an outright end to the Islamic practice of stoning adulterers. By contrast, liberal writers sneered at the Somali-born human-rights activist Ayaan Hirsi Ali as an “Enlightenment fundamentalist.” Brandeis disinvited her to speak on campus in 2014. The Southern Poverty Law Center last year branded her an “extremist,” along with the counterterror campaigner Maajid Nawaz. Liberals thus empowered the most illiberal elements of Muslim communities while marginalizing reformers. Is it any wonder that many voters came to see Muslims as sources of danger and social incohesion? Liberals, finally, “won” the debate over nationalism. In Europe especially and the U.S. to a lesser extent, they treated nationalism and the West’s Judeo-Christian heritage as relics of a dark past. For European Union leaders, the ideal political community was an ever-expanding set of legal procedures, commercial links and politically correct norms. Citizens could fill in the blanks with whatever cultural content they preferred—preferably “Europe” itself. But norms and laws didn’t inspire political attachment. The hunger for authentic identity drove young European Muslims to the Islamist underground. Among native Europeans, the far right came by default to own nationalism and nationhood. The divergence proved poisonous. Judging by their breathless editorials and social-media outbursts, leading liberals still blame this reversal in political fortunes on a paroxysm of collective fear and hatred, the forces they’ve always sought to banish. Yet the main culprits for the popular revolt against liberalism are liberals themselves. If liberal ideals are to survive the current backlash, the West needs sharper, more hard-headed liberals.

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