Abraham Lincoln is a war criminal.
States should be allowed to secede and not be persecuted.
If the Federal Government violates its restrictions enforced by the Constitution then it has violated the contract and a state has the legal right to secede from the union. The Federal Government is an evil aggressor if it, in response to violating its own contract to govern, declares war on a seceding state or sends armies against it.
Not really the case for the US. Most states are the size of other countries.