Constitution says the Federal Govt can collect taxes. Last time I checked, the ATF was the Federal Govt. Their NFA tax may not be governed under the laws set by Congress on tax, but nonetheless, the NFA stamp of $200 is a federal tax. Thus its a uniform tax.
Play the NFA game, pay the tax.
So yes, my examples are relevant to federal uniform excise tax.
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The Congress shall have Power To lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts and provide for the common Defence and general Welfare of the United States; but all Duties, Imposts and Excises shall be uniform throughout the United States;