From my perspective I was giving a counterexample to challenge the claim that all theft is unlawful.

You're saying that if legal money collection benefits society it is "tax", but if it does not benefit society it is "stealing"? Sure, if you split the words that denote legal money collection into these two forms, then tax is not theft. I simply define tax as legal money collection.

I'm not anti-tax, btw, but neither do I subscribe to the view that just because a government passes a particular money collection law that it's a just law.