Many people would call such thinking extremist, but I don't think it is. I think being ready for it is just sensible. Living in terror of it every day is stupid though, anxiety will get us nowhere.
History teaches us though, that few things are really impossible. There were people in Rome that thought the republic would last forever, then Caesar took over. People in Germany never thought Hitler would go so far as he did. The Czars of Russia never thought the people would revolt and defeat them, etc. Living as though nothing wild can happen just leaves you unprepared. We obviously can't be prepared for everything, but the things we know about we can at least try to be. Trouble will ALWAYS be prepared for you, but how often will you really be prepaired for it? Why do people think others are extremists simply because they choose to be ready for events that are beyond most people's ability to react? Ever see those flood victims or tornado victims on TV saying, "We never thought this could happen to us!". The ones that did had shelters and got in them. This is no different.
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I twist the facts until they tell the truth. -Some intellectual sadist
The Bill of Rights is a document of brilliance, a document of wisdom, and it is the ultimate law, spoken or not, for the very concept of a society that holds liberty above the desire for ever greater power. -Me