That's when it gets real.
No warning, no central command, fire-and-forget 30 minutes to target hypersonic cruise missiles traveling at 20 times the speed of sound. It will be over before you can shave and brush your teeth and lay down in your bed. These weapons are so precise they do not go off until 4 meters before they hit ground zero with a one meter margin of error or exactly 500 meters for airbursts dead center over target.
There is only one thing that civilians can do for their own safety and that is lock the hatch behind them inside a vault. Everything else is just navel gazing gibberish.