Read the paragraph. In the 1800s, Henry Clay took part in key events of US history. He was one of the War Hawks who called for war with Great Britain—a war that President James Madison declared in 1812. In 1814, Clay was one of the signers of the treaty that ended the conflict. After the war, Congressman Clay supported an economic plan known as the American System. It called for high tariffs, a national bank, and improvements to transportation. Clay also helped bring about the Missouri Compromise in 1820 and the Compromise of 1850. These agreements dealt with the spread of slavery to new states.

What key detail supports the idea that Henry Clay affected US foreign relations in the 1800s?
He signed the treaty that ended war with Great Britain.
He wanted the establishment of a national bank.
He called for improvements to transportation.
He helped bring about the Missouri Compromise.