How much money of yours is needed to be owned by someone else for it to be slavery? 10%? 90%? 100%? 50%?
Taxation is Constitutional.
Why is taxation unconstitutional? The constitution limits the powers of the government, but besides fighting the British, it was collecting taxes was needed to fund the army.
Ah, I would say it isn't perfect, but a constitution is itself essential to freedom. A constitution is a document that limits and describes the powers of a governing body.