What is the topic sentence in this paragraph? Alexander Hamilton’s major role in the US government was secretary of the Treasury. He used his position to generate income to strengthen the federal government’s power. After the Revolutionary War, the new government needed a way to pay its debts, and Hamilton created several plans to make this happen. One plan involved a tax on luxury goods. Another included buying and selling bonds to private investors. Hamilton wanted to establish a national banking system using one currency, which would help bring the states together as one nation.