The power has been out in Northern California. More than 1 million Californians were without electricity, one of modern life's essentials that is frequently taken for granted. The blackout was done on purpose—to prevent sparks from powerlines that could ignite deadly wildfires.

On the surface, the blackout and its causes are simple to understand. But the deeper causes are complicated, span decades of public policy, and dozens of overlapping unintended—and intended—consequences of decisions, both related and unrelated.

The wind in Northern California is blowing in from dry Nevada, as it often does this time of year. It's called the "Diablo wind." In Southern California, the comparable current blowing in from the Mojave Desert is known as the "Santa Ana winds."