Sort of. The US Supreme Court ruled in US Term Limits Inc., v Thornton, (1995) that states can't pass laws or state constitutional amendments imposing term limits on US Senators and Congressmen because it violates several portions of the US Constitution (Article I, Sections 2 and 3 and the Seventeenth Amendment). The states also can't override the US Constitution, per the Article VI Supremacy Clause.
This decision only affects members of the US Senate and House of Representatives, however. States can set whatever term limits they like on state and local politicians.
Congress and the states can work together to establish term limits for Senators and Representatives by amending the Constitution, just as the office of President was constrained to two terms by the Twenty-Second Amendment (1947).
No.
Population.
The Court ruled that the Espionage Act was constitutional.
illegal
No. It has been ruled constitutional.
It is not unconstitutional. The Supreme Court ruled that it is constitutional.
The Supreme Court ruled that Nixon had to expose his secret tapes.
The Supreme court ruled out the teaching of religion in public schools and segregation.
In the 1905 Lochner v. New York case, the Supreme Court decided that states could not set limits on the hours that bakers could work.
The Court ruled that the Espionage Act was constitutional.
it can be used in some situations
The Supreme Court ruled that the death penalty could only be used in cases involving murder.