How would a secessionist use slavery to construct an argument defending a states right to leave the union?

southern states had only ratified the constitution after an agreement with the north that slavery would never be abolished.

slavery had been listed in the declaration of independence as an unalienable right that no government could violate.

slavery had been accepted at the time of constitution when the union was created; therefore, if slavery was abolished so was the union.

if legally owned property, like slaves, could be abolished by the national government, states could secede to protect their rights.

union blockade

explanation:

the union blockade in the american civil war was a naval strategy by the united states to prevent the confederacy from trading.

the blockade was proclaimed by president abraham lincoln in april 1861, and required the monitoring of 3,500 miles (5,600 km) of atlantic and gulf coastline, including 12 major ports, notably new orleans and mobile. those blockade runners fast enough to evade the union navy could only carry a small fraction of the supplies needed. they were operated largely by british citizens, making use of neutral ports such as havana, nassau and bermuda. the union commissioned around 500 ships, which destroyed or captured about 1,500 blockade runners over the course of the war.

it granted civil rights to african americans.

companies passed on production and transportation costs to consumers