The 27 national leaders of the European Union love to extol the solidarity that binds their countries together.

Even the words signal destiny. "Union” comes via French from the Latin unus for "one,” and solidarity from solidus for "firm, whole and undivided.” Like a good marriage, the bloc is meant to be a solidarity union.

In reality, it is no such thing, and Europe’s enemies know it. That includes Russian President Vladimir Putin and autocrats in China and afield. The EU’s biggest problem is the inability to see threats, responsibilities and sacrifices as shared.