Why do you lock your doors?

Good point. But my personal experience would amend that to "Most people are good," or "few people are evil." And that's the way I generally have acted in life, starting out on the assumption that a person is good, until I see otherwise. In fact, we don't always lock our doors, and I rode my bike all around town for over 25 years without locking it.

Overcrowding and lack of resources do seem to lead to competition, and more antisocial behavior. People in a big city will lock their doors, especially in an oppressed section of town, and especially when the economy is down. Not so much in a small town.

Laws and rules are needed even between good people, as opinions may vary. We have a law here that people drive on the right side of the road. It's not necessarily that driving on the left is wrong, just that the law codifies the agreement that we have made locally.

Unfortunately, there is even disagreement between nations as to what is right. While it would be nice to have a moral authority that all would accept, I don't see that happening soon unless aliens land tomorrow, or Christ returns. We make do with the tools we have, and that includes the military, as well as diplomacy.

Not all people are good, so you have a lock your door, simple as!

so I have time to get my shotgun