Why do states have to follow certain federal rules?

The supremacy clause contains what's known as the doctrine of pre-emption, which says that the federal government wins in the case of conflicting legislation. Basically, if a federal and state law contradict, then when you're in the state you can follow the state law, but the feds can decide to stop you.

Explanation:

this statement is true.

forests are public goods, available for everybody. when usage of such a good becomes interesting for consumers and its usage increases, there can be a risk of overexploitation. it is a non rival good therefore, if one person consumes the good it does not reduce the availability for subsequent consumers.

these caracteristics require the establishment of measures in order to prevent the destruction of a commonly owned space, for example, to restrict the amount of people that have access to the same time.

american political culture includes a plenty of focus views and preferences. not all westerns experience the same opinions, of course, but the large preponderance promises to these general ideas, including equality, justice, freedom, individualism, integrity, and difference.

the united states is a democratic republic. residents elect representatives to governmental, nation, and local administration; those deputies create the regulations that command u.s. community. although emptiness in u.s. law needs it, in usage, the administrative system is ruled by executive factions.