Especially considering that retail sales taxes are indirect taxes laid uniformly, i.e. with the same rate and law without regard to location in the United States, a tax definitely within the powers of Congress to lay and collect under Article I, Section 8, clause 1 of the Constitution.
Dang -nobody tells me anything around here, why am I always the last guy to get the news!!!
I tell you what, I share my link about the sales tax ruling if you share me your link that says the SCOTUS is now making sense and is following the Constitution.
Amazing, --learn something new every day...