First off, the U.S. grew enormously in size. It physically expanded over time and did not always have the land it has now. The Louisiana Purchase is one of the most famous bargains in American history as it expanded the U.S. by a third more. In document A it explains how they purchased the land from France for a mere 15 million dollars. It was a huge expansion for the country. Also, West Florida and East Florida was ceded from Spain to the U.S. These were not the only territorial acquisitions made, as there was acquisitions made for Oregon Territory, Texas, former Republic of Texas, and much more. This land and inquiries are what made the U.S. such a big country.
Furthermore the United States grew politically. Three branches of government is how the government works and was introduced in The Constitution of the United States of America in 1787 (Doc D.). The three branches are legislative branch, executive branch, and judicial branch. These branches were made up of different people and parts of the government. "...the constant aim is to divide and arrange the several offices in such a manner as that they may be a check on the other.... (The three branches) should not be so far separated as to have no constitutional control over each other," James Madison wrote in the Federalist Paper #51 (Doc. D). Also, Andrew Jackson made sure that all executive power would be vested in the President of the United States." (Doc. F) All decisions in the executive branch could be made or vetoed by the president. Politically the U.S. was shaped into how it is today.
Lastly, U.S.A. grew socially. The U.S. started becoming not only