Looking at "taxation is theft" from both sides

(Previously published in The Libertarian Enterprise)

Statists hate the "libertarian shibboleth" of "Taxation is theft". It makes them lose their minds and fling poo before running away screaming profanity.

As amusing as making them that crazy is, it may not be constructive... so, let's really examine the idea.

"Theft" is the act of taking property that belongs to another without their consent- with or without the threat of violence.
"Theft" is almost universally condemned. No one claims the future use of the stolen property justifies the theft.
"Taxation" is the act of taking property (money) that belongs to someone else without their consent- enforced by the threat of violence.
"Taxation" is almost universally justified by imagining what the stolen money will (might) be used for.
Therefore, "taxation" is theft.

Or... let's turn it around and look at the argument from the statist perspective:

"Theft is the taking of property non-voluntarily.
Taxation is voluntary; people would pay even without penalties.
Therefore, taxation is not theft."

Which one holds up better to scrutiny? How true are the individual premises and conclusions in each?

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