How does taxation differ from common theft?

[x2000]

#1 You can reject the notion all you want, but you still have to pay for a national defense, cops, and the fire department at a bare minimum.

Edit to add: So you want our nation defense to be paid for by 100% voluntary payment system? You say it's outside the scope of the question, but it's not. Then you go on to say, "I will just say that by allowing payment collected by threat of violence opens you up to the money so collected not being used for its stated purpose."

The reason is simple. People will not pay their fair share if given a choice.