When I hear about “double taxation” in the U.S. I think of the taxation of corporate profits combined with income taxes. For capital invested in stocks, I am taxed twice on any income derived.
Also, if, as a majority shareholder you appoint yourself as the CEO and pay yourself a salary, it is tax deductible for your company, so money that goes to your salary is taxed only once.
When I hear "double taxation" in the US I usually think first of self-employed people sometimes having to pay both income and payroll tax compared to an otherwise employed person only paying income tax.
Then maybe I think about places like Missouri where after you take your post-tax income and buy a car with sales tax on the purchase, you pay yearly for that car as a personal property tax (which does not include your license plate, or inspection, or the city sticker some local places require).