Chinese Army hacking US infrastructure

The Chinese are becoming more aggressive in their computer attacks on the US. With attacks on major newspapers uncovered and power grids being pinged by the Chinese military we are looking vulnerable.

From a recent NY Times article: 

It makes me wonder why we allow computers to control the power grid to the extent that they do now. If we want to make our country less vulnerable, wouldn't it be smarter to dumb down these grids? After all, didn't we have power grids fifty years ago? Maybe they weren't as efficient as they are now with the networking. Still, how about a back-up system that takes the grids off-line and allows them to run, albeit slightly less efficiently when they perceive they are under cyber-attack?

Seems like a way to stay a little safer in a dangerous world.