Why was it possible for the North and South to compromise over the div

Why was it possible for the North and South to compromise over the divisive slavery issue in 1820? What “lessons” do you think the North and South learned from the Missouri Crisis?

What will be an ideal response?

ANSWER
Consider:
Compromise: passions over slavery were not yet so aroused; antislavery advocates were not yet well organized; attention was diverted by the Panic of 1819; there was enough western real estate to divide between the two sides
Lessons: Northerners learned that the South intended to expand slavery (and maintain its hold on national political power); Southerners learned that they would have to present slavery as a positive good to justify its expansion