The extension of slavery into the western territories.
For a specific instance, see the landmark supreme court case Dred Scott v. Sandford.
Answer:
A rebellion broke out and John was ordered to appear before his overlord, Philip II of France. His failure to do so resulted in war. By 1206, John had lost Normandy, Anjou, Maine and parts of Poitou. These failures were a damaging blow to his prestige and he was determined to win them back.
Explanation:
It's began with the Spanish American war
The president because he can veto a bill he cant pass a bill