Also we can plug a electric blanket with tiny wires that get kicked and pushed around all night into a outlet that is protected with a 20 amp breaker. Years ago I called my insurance company and told them "I know this sounds unbelievable but my electric blanket caught fire." They replied no problem, quite believable. We get a tremendous amount of clams for fires started by electric blankets and electric coffee makers.
That's why I got rid of my electric blanket, and won't buy another. Mine never caught fire, but I've heard too many horror stories, and the risk seems too great to me. Better to insulate your bedroom and use a regular heater.