I have spent enough time in the hallways of Brussels to know that the air has changed. For decades, the European Parliament operated on a gentleman’s agreement: no matter how much the center-right and the socialists bickered over tax codes or carbon targets, they stood together against the fringe. This was the famous 'cordon sanitaire,' a political quarantine designed to keep those who would dismantle the European project away from the levers of power. But walking through the Espace Léopold today, you can see the masonry crumbling. The firewall hasn't just been breached; it’s being dismantled by the very people who built it.

We are witnessing a quiet, methodical normalization of the radical right. The traditional center-right power brokers, long the guardians of the institutional status quo, have realized that their historical allies on the left are no longer enough to secure a majority. Instead of moderating their stance or seeking compromise, they are looking to their right. They are co-authoring legislation and coordinating votes with factions that, only a few years ago, were treated as pariahs. This isn't just tactical maneuvering; it is a fundamental shift in the continent’s ideological gravity.

The European Union was never just a trade bloc; it was an insurance policy against the darkest impulses of the 20th century. It was founded on the radical notion that no majority, no matter how loud, should have the right to define who belongs and who does not. By inviting the far right into the room—not just as observers, but as architects—the mainstream is setting fire to that policy. When the center colludes with parties that fundamentally reject the rule of law and cross-border cooperation, they aren't 'taming' the radicals. They are being consumed by them.

This is not a drill, and it is not an exaggeration for the sake of an op-ed. When I talk to officials now, the conversation has shifted from how to stop these movements to how to accommodate them. They argue that the voters have spoken, and that democracy requires inclusion. But democracy without a commitment to the foundational principles of the union is just a slow-motion collapse. If the centrist coalition continues to trade its soul for a few legislative wins, they will soon find that they have built a house they no longer recognize, governed by rules they can no longer control. The firewall is gone. The doors are open. And the guests are moving in for good.