Electricity. Cut off the electricity and America immediately falls apart. Three days without electricity and people start dying from the heat or cold, and the lack of fuel, water, food, and medications. The police cannot function, banks close, credit and debit cards won't work, and cash vanishes from circulation. Stores run out of baby formula, baby food, and diapers. Nursing homes and hospitals run out of fuel for back up generators, medical equipment shuts down, and people quickly die.

Be it hackers, foreign countries, American rebels, corporations or criminals, someone is going to figure out how to shut the electricity off in America - and when they do, we're done. .