Our nation and logistics are so entangled and interconnected, a serious conflict in any location would result in economic consequences, not to mention that the market hates uncertainty and instability. It's better for the economy if the sheep remain sheep.
Otherwise, any plan folks may have for protecting and defending themselves is not a bad idea, but the plan is usually the first casualty of war. The ability to recognize threats or opportunities and adapt in the field would be the key to survival. That doesn't mean that someone with everything figured out today, might not be 800 miles from home, eating grass, counting rounds, and wondering what the heck they are going to do after 90 days.
You are correct, and hopefully we never have to find out, because some people will get a rude awakening when they are forced to understand what war is really like. We have been blessed it has not come to our shores in a massive scale for a very long time.