Russia’s unprovoked invasion of Ukraine came as a shock to Americans, most of whom have never lived in a world where one European nation invades another.
But for students of history, it is actually the fragile peace, secured by NATO and the liberal world order, that is the historical anomaly. Democracy in so many nations, peace among neighbors and the free flow of goods and supplies across borders stand in stark contrast to human history, one marked by empire and conquest and war.

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