The citizens of the United Kingdom have voted to leave the European Union.
In doing so, they have undone a half-millennium of work toward pacifying the most war-torn continent on the planet earth.
Europe has always been at war with itself. The Pax Romana never fully pacified the Germanic tribes. Strife was frequent through the Middle Ages. The battle of Agincourt solidified enmity between the English and the French.
The Thirty Years War was one of the bloodiest conflicts in the history of mankind. The Napoleonic Wars shook the world. And the world wars of the 20th century killed about half as many people as had existed on the entire planet at the time Julius Caesar conquered Britain for Rome 2,000 years earlier.
After many of these wars, there were attempts to achieve peace among the war-torn nations of Europe. The Peace of Westphalia, the Congress of Vienna, and the Treaty of Versailles all aimed to create a peaceful European system.
They all failed.
Out of the ashes of the most brutal and most recent world war, and in the shadow of an even more frightening potentially nuclear Cold War between its victors, emerged an alternate vision of what the home of Western civilization could become.
After a world war that killed at least 50 million human beings and left the nations that invented modern industrial civilization a pile of rubble, the victors (at least in the West) nurtured a new world of collective security anchored by economic, cultural, and political ties that could never be sundered.
Until this Thursday.
The EU is a deeply flawed and poorly assembled pile of self-contradictory institutions. This is also true of every one of the 196 nation-states currently recognized by the UN. Every citizen on the planet deals with a government that seeks to represent their interests but has its failings. The people of the UK face no less of a tussle with their own representatives in Westminster than they did until this week with their representatives in Brussels.
But despite its flaws, the EU and organizations like NATO have to this point achieved an accomplishment not seen in a 1,000 years: peace in Europe.
The EU is not a perfect entity. Much more could be done to ensure a true continent-wide state. As we’ve seen with repeat crises in Greece, there needs to be a better balance between monetary and fiscal policy across Europe. Issues of regulation and immigration that were among the major complaints of the Leave campaign can be dealt with better.
But the people of the UK have abandoned any means of addressing those issues, and of furthering the common goal of peace and prosperity that the EU has as its unattained promise, by choosing to turn away from their continental peers.
In the days after that decision was made, we have already begun to see some of the chaos that will likely intensify over the next several months and years as the long and painful process of negotiating Britain’s exit from the EU begins. The pound has collapsed, global markets are in turmoil, and a UK, and possibly more widespread, recession appears very likely.
In the longer term, Brexit represents a huge challenge to the ideal of a peaceful and united Europe, and that may prove to be a tragedy for the world.