The abolitionist movement was very powerful in the North, since the North did not rely heavily on a slave population and because slavery had long-since been depleted in the region.
Legal right that a court has to receive a case first. For example, the Constitution makes it clear that the Supreme court has 'original jurisdiction' when states sue states and in cases involving high-level diplomats.
Answer:
After the fall of the Nazi Regime, the nations liberated by the USSR after the war had not been liberated at all but integrated as satellite countries (puppet-states) for the USSR called the Eastern Bloc. Communism was on the rise after the end of fascism and Stalin wanted to convert as many countries to communists as possible. The Warsaw Pact was also established to rival that of NATO and further integrate Eastern Europe into Communism. The Cold War had been a game of deception and bluffing so if the democratic side failed to keep up with Communists there would be Europeans leaning to be communist.