defend this claim, will give brainliest to resoniable answer

Answer:
first of all, close some tabs there bud.
and the Mexican American war made it to where a new state,(Texas), joined the party and they were a slave state and the then easily tipped balance was tipped in the favor of the south. so the north made a bunch of new rules that really ticked off the south, eventually when Lincoln won the presidency, South Carolina,(my home state), then the rest of the south followed suit