Paul Craig

The globe has always been a world of walls, from the Great Wall of China to Hadrian's Wall to the Berlin Wall. But a new age of isolationism and economic nationalism is upon us, visible not just in Trump's obsession with building a wall on the Mexico border or in Britain's Brexit vote but in many other places as well. China has the Great Firewall, holding back Western culture. Europe's countries are walling themselves against immigrants, terrorism, and currency issues. In fact, at least 65 countries have barriers along their borders. Understanding what is behind these divisions is essential to understanding much of what's going on in the world today.

Different branches of the same religion are the exception more than the rule, and they have had a profound impact upon history. The schism between the Orthodox and Catholic Churches influenced relationships between nations across Europe, and religious intolerance based on different Christian faiths led to persecution and outright violence across the continent for centuries.