Question

How did a high enslaved population in the southern states threaten the people of the northern states?

It meant the exported crops would primarily come from the South.
It made it much harder to put an end to slavery.
It pressured the free states to reconsider the issue of slavery.
It potentially gave the South more power in the government.

Answer 1

It potentially gave the South more power in the government.

Because enslaved people were partially counted for representation (the Three‑Fifths Compromise), states with large enslaved populations gained extra seats in the House and more Electoral College votes, letting the South block anti‑slavery legislation and influence national policy.