I'm not so sure about your view of Europe. I agree that a large scale war in Western Europe, especially involving Germany like the ones in the 19th and first half of the 20th century seem extremely unlikely. But Europe is larger than that.

The war in Yugoslavia was not so long ago, for one thing.

For another, Hungary got itself a nice extreme right regime that seems rather keen to transform the country into an authoritarian state. What if they decide, at some point, that the land occupied by some of the Magyars in neighboring countries should really belong to Hungary again?

Keeping the peace in Europe is far from a finished project.