We are not. At least that is not how we were established.
"There is no maxim in my opinion which is more liable to be misapplied, and which therefore needs elucidation than the current one that the interest of the majority is the political standard of right and wrong.... In fact it is only reestablishing under another name and a more specious form, force as the measure of right."
~ James Madison, Letter to James Monroe, 1786