Taxation is theft but it's a necessary theft. Since it's necessary, we elect representatives to police the theft. Their job is to keep it as small as possible and ensure the theft benefits the common good. If the theft becomes too high, we replace those guards with new ones.

All government is a necessary evil. The left always forgets the evil part and the libertarians always forget the necessary part. We can argue over how necessary and evil certain programs, functions or departments are but government itself is a necessary evil.

Personally, I think the founders struck a good balance on the limits of government and provided needed tools to help cage the evilness. Over the last 200 odd years the Beast has grown and should be put on a diet before it breaks out of it's cage altogether.