No, but they are the smallest form of government who doesn't rely on some other form of government for its existence.
States exist because the Constitution (and one or two other things) say they exist. The US government cannot pass a law abolishing Missouri, even if everyone really wants to. Missouri, however, can change its county structure, abolish cities, etc. Because the very existence of those forms of government depend on the existence of Missouri.
By design, the US is a federation of more-or-less sovereign States. "Laboratories of Democracy" and all that.
It doesn't really make sense to have proportional representation at any level smaller (or larger) than the individual state.
States exist because the Constitution (and one or two other things) say they exist. The US government cannot pass a law abolishing Missouri, even if everyone really wants to. Missouri, however, can change its county structure, abolish cities, etc. Because the very existence of those forms of government depend on the existence of Missouri.
By design, the US is a federation of more-or-less sovereign States. "Laboratories of Democracy" and all that.
It doesn't really make sense to have proportional representation at any level smaller (or larger) than the individual state.