Answer:
the Abbasids
Explanation:
In 750, the Abbasids, a rival clan to the Umayyads, rose to power and overthrew the Umayyad Caliphate. They took control and formed the Abbasid Caliphate which would rule much of the Islamic world for the next several hundred years.
One very famous, perhaps the most famous way was through improvised vaccination. Specifically, George Washington ordered his healthy men to be injected with substance taken from the wounds of the sick men during a smallpox infection.
A risk was that those men would get sick just like the the sick men did, but the the potential reward would be that they would get sick in a controlled way and that they would be able to fight this disease.
If you're referring to the Civil War era, in the years leading up to the war, once such compromise could have been that slavery could continue to exist where it was, but not spread to other states.
All of the countries were having a battle of who could build the biggest bombs, guns, tanks, weapons, technology, etc. which created tension between rival countries. everyone was afraid of the next country being too powerful. Hope it makes sense :-)
