The Missouri Compromise of 1820 did not have lasting effects. Which is the best explanation for this?

Question

A. The compromise relied on popular sovereignty, and public opinion was overwhelmingly opposed to it.
B. The compromise limited the number of states that could be admitted per year, so it could not be enforced.
C. The compromise only applied to the lands of the Mexican Cession, so it quickly became irrelevant.
D. The compromise only applied to the lands of the Louisiana Purchase, and a later law effectively overturned it.

Answer 1

The best explanation for why the Missouri Compromise of 1820 did not have lasting effects is:

D. The compromise only applied to the lands of the Louisiana Purchase, and a later law effectively overturned it.

The Missouri Compromise was significant in addressing the balance between free and slave states within the territories acquired from the Louisiana Purchase. However, it was eventually undermined by subsequent legislation, most notably the Kansas-Nebraska Act of 1854, which introduced the concept of popular sovereignty, allowing new territories to decide for themselves whether they would be free or slave, thereby effectively invalidating the previous compromise.