Americans and Europeans tend to think it is self-defeating to engage in cyberattacks on private companies in a foreign country. You may learn something, but you destroy the trust that lubricates free exchange. Pretty soon your trade dries up because nobody wants to do business with a pirate. Investors go off in search of more transparent partners.

But China’s cybermercantilists regard deceit as a natural tool of warfare. Cyberattacks make perfect sense. Your competitors have worked hard to acquire intellectual property. Your system is more closed so innovation is not your competitive advantage. It is quicker and cheaper to steal. They will hate you for it, but who cares? They were going to hate you anyway. C’est la guerre.

In a brutality cascade the Chinese don’t become more like us as the competition continues. We become more like them. And that is indeed what’s happening. The first thing Western companies do in response to cyberattacks is build up walls. Instead of being open stalls in the global marketplace, they begin to look more like opaque, rigidified castles.

Next, the lines between private companies and Western governments begin to blur. When Western companies are attacked, they immediately turn to their national governments for technical and political support. …