Have you ever seen a photograph of the earth at night? Lights are scattered across the globe, wherever human beings live and work and prosper. But there is a strange blank shape at the top of the Korean peninsula, all the more remarkable because the lower half of the peninsula, South Korea, is a blaze of luminosity. The dark patch above it is socialist North Korea, where the people live in such desperate poverty that their country is dark at night. The one tiny point of light is Pyongyang, where party elites enjoy the fruits of the miserable labor of the North Korean people, who are essentially slaves. Otherwise, North Korea is simply dark.

The illuminated lower half of the peninsula offers us a vision of what the world looks like with freedom—the freedom to create, prosper, and, as is so obvious, even to illuminate. But you also have in that photograph an image of what the world might look like were the torch of human liberty to sputter out, casting civilization into darkness.

Surely, some will say, the possibility is only alarmist rhetoric. Surely things will go on as they ever have. Has it not been always thus?

In response to that question I would merely point to human history. The lesson is plain. Civilizations fail. The reason they fail is also plain. When civilizational virtues are eroded from within, people lose the capacity to defend the good things those habits enabled previous generations to achieve. Think of ancient Greece; or the Roman Empire; or Germany in the 1930s. There are many other examples.