It takes immense courage to stand up to the primary terrorist funding organization known as the IRS - and I commend you for doing it.
There are some other 'Natural Law' methods that can show that Involuntary Extraction of Currency to be Unlawful.
No one can take anything from you without your consent. Not even if they have a blue suit and badge. Even IRS Directors and House/Senate member have been recorded many times mentioning that Taxes are voluntary. It's a fundamental aspect, tenet, and foundation of Natural and International Law.
Without Agreement there can be NO CONSENT. The two words go hand in hand. If you agree to taxation than you consent to taxation. But, agreement is like a contract in that there are several elements to a 'valid' contract.
Mutual Understanding (meeting of the minds), and implied or expressed agreement are required. But, ALL regulations are written in legal-ease, and the common man has been told on thousands of occasions that we cannot make legal determinations, hence we cannot understand legal-ease. Legal-ease English is NOT the same as Plain English and therefore we can neither understand it nor can there be a valid contract. Imagine a Russian and Brazilian (neither who read in English) agreeing on a contract written in English. Even if they both sign it, doesn't make it valid, because they both interpreted the meaning differently.
No valid contract intends injury to a 3rd party. There is plenty of evidence over the years of the American Military Industrial Complex killing innocent children, women, and men in offensive attacks around the world, hence we have a moral imperative to NOT agree to taxation.
There must be Due Consideration. I personally have sent the IRS dozens of letters asking them specifically how my previous tax dollars were spent, and I have never been given even a single answer. Even the Grace Commission (which was a Presidential Executive Order) report admits that not a single nickel of federal taxes are spent on the types of things that the taxpayer would benefit from. I personally have no evidence of any benefit from the IRS.
Transparency. The IRS requires tax payers to spend thousands of hours and/or thousands of $$$ each keeping track of income, yet has not once (that I have ever heard of) given the equivalent breakdown of how the money was spent. Without a Due Consideration Clause in the Contract it's not valid, and if your not given the transparency to prove the elements of the contract have been met, than it's a Breach of Contract/Trust.
If Government is using the 'Duty of Allegiance' for 'Duty of Protection' as the reasoning for taxation, then remember that the courts have ruled numerous times that the Police have NO DUTY OF PROTECTION. Therefore, there is NO duty of Allegiance.
IMHO