Lesson 3: Unity and Sectionalism

Key Idea

After the War of 1812, a wave of patriotism swept the United States. With only one major political party, this period of national unity became known as the "Era of Good Feelings." Americans felt a stronger sense of shared identity and purpose.

To build a stronger, self-sufficient nation, leaders like Henry Clay promoted the American System. This economic plan used a national bank and protective tariffs to support industry. It also funded new roads and canals to connect the growing country.

Key Idea

As the country grew, questions arose about who had more power: the states or the national government? The Supreme Court, led by Chief Justice John Marshall, provided answers that strengthened the nation.

In one major case, the Court ruled that a state could not tax the national bank. In another, it decided that only the federal government could control interstate commerce—business that crosses state lines. These decisions established that the federal government had power over the states in certain matters, helping to unite the country under one authority.

Key Idea

In the decades before the Civil War, the North built an economy based on industry. Factories in growing cities produced goods, and new railroads connected these areas to farms in the West. Many factory workers were recent immigrants.

The South’s economy, however, remained focused on agriculture. Its wealth came from huge plantations growing cash crops like cotton. This entire system depended on the forced labor of enslaved people.

Key Idea

As America expanded westward, the fierce debate over slavery grew with it. When Missouri applied to become a slave state, it threatened to upset the fragile balance of power between free and slave states in Congress. The nation faced a serious crisis that could have split it apart.

To avoid a disaster, Congress agreed to the Missouri Compromise of 1820. This deal admitted Missouri as a slave state but also admitted Maine as a free state, keeping the numbers even. It also drew a line across the western territories, banning slavery north of it.