It always amazed me how self-centered some people are. Let me kill this dude for his shoes - rather than - let me blow this guy away with a .50 cal before he successfully attempts to take a American life.
.50 cal is WAY better. Just watching a dudes head burst like a cherry when the round misses is worth it.
When people can actually PROVE there has been a significant change in the last 200 years, then that's when you should worry. Let's not forget that 30 years ago people were worried about global COOLING.