But history never ends. And nearly 30 years later, the concept of the West is once again up for grabs as Trump tries to redefine its meaning.

I was reminded of this when I visited Europe during the spring and was immediately struck by the visceral politics rocking the continent and a deep sense of uncertainty about whether America would remain a stabilizing force.

The best way to see how the searing events of the 20th century and Europe’s compact geography delivered us to where we are today is to take a train. Climb aboard a Eurostar under the steel arches of St. Pancras station in London and history spools before your eyes like a movie.

Cutting south through the county of Kent, you race under blue skies where Royal Air Force and Luftwaffe pilots jousted in 1940 during the Battle of Britain, which changed the course of the war.

Soon, the train slopes into the Channel Tunnel, which will remain open after the UK leaves the European Union – a monument to a time when an island nation wanted to physically tie itself to the continent.

After zipping into the French sunshine, the train scuds across the battlefields of two World Wars. Now and then, an allied war cemetery flashes past, its white headstones arranged in neat rows. If you’re headed for Paris, you’ll cross lands fought over at the Battle of the Somme in 1916, which cost nearly 60,000 allied casualties on its first day alone. Head east and change trains in Brussels for Germany and you’ll go through Aachen, the first German city seized by allied troops in World War II after a battle that cost both American and German forces more than 5,000 casualties.

The carnage was so appalling that post-war leaders vowed the continent would never again be allowed to tear itself apart and plunge the world into war. That resolve led to the rise of institutions including NATO and the European Union. The US effort to rebuild Europe in its own democratic image, known as the Marshall Plan, will celebrate its 70th anniversary next year.

Nowhere is this history more resonant than in Berlin, a city divided in 1961 when the Communist East erected a wall that carved neighborhoods in two and imprisoned its own population.

Today, Berlin is a cosmopolitan capital still reveling in the freedom it was denied for so long. Most sections of the wall are long gone. Here and there though, pieces survive, daubed in colorful graffiti. An East German watchtower still stands on one side street, surveying explosive redevelopment where communism once reigned.