From Check Your Premises we get What is self-defense? Part 2.  I think this is an important issue for us all to consider.  You can read the previous discussion by following his links. 
As I said in his comments, I don't usually consider verbal threats to be very serious, even if it is possible for the threatener to follow through.  I have had several people make threats towards me during my life, but have yet to have someone really try to carry the threat out.  Perhaps it is because I made it clear that I would defend myself if they tried.  Perhaps it is because they cooled off or decided I wasn't worth the effort.  Whichever, it means I have not been backed into a corner yet.
I realize that the state is a different critter: it threatens by its very existence, and it does carry out the threats against selected victims.  Therefore, I think self-defensive actions are justified, if not always wise.  I think it is usually easy to escape notice by the state, but I don't expect or demand anyone to live their life as a scurrying rodent hiding from a predator.  I guess this is another case of wishy-washy "do what you like": confront, scurry, scheme, "gulch", or strike back.  What is right for me may not be right for you in your current circumstance.
I do think that government is irredeemably evil, but I refuse to live my life worrying about what its agents or enforcers think about me.  Government: disgusting, morally vacant, harmful to life and liberty, and never to be trusted with even the smallest power, but still almost completely irrelevant.  Until something changes, I don't feel intimidated by them and I hope it stays that way.
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