1. North Korea will never be able to launch an attack on us.
2. As far as your friend, I dont think a garbage can will protect and electronics should be his last concern.
To be prepared he will need a food source (not sure if he lives in the country or city/suburbia)
1. He should be more concerned with a 1 year food supply for him and his family and/or be able to hunt and fish along with a couple hundred million other Americans.
2. He will need a source of water, if he doesnt have city water and has a private well, then some inexpensive solar panel to hook up to his well might work.
3. He will need plenty of guns and ammo and be willing to shoot anyone who wants his food and water (including friends and family).
AS people start starving, word will get out and he will have to defend it or run.
There will be a break down of government and law enforcement, gangs will roam the streets, going house to house and taking whatever they want, unless you and your neighbors can defend yourselves.
4. There is also an in-between and in the past what has made this country great, people come together and do the right thing but there is no way to know until it happens and if it happens, it wont be that way all over the country.
But if all he has is electronics in a garbage can, I think he needs to think a little deeper.
)