Hub says:

Hamilton wanted the U.S. to have a commercial and industrial economy, as opposed to the agricultural economy favored by the southern states and settlers in the west.

One reason he thought this was important was that he believed the U.S. would have to defend itself, and that an industrial base would provide a means to do so. He also was a disciple of Adam Smith and believed that commerce and industry would help preserve liberty more than than would a slave-based economy.

He thought that the U.S. had to repay the debts run up by the Continental Congress or no one would ever loan money to the U.S. So he was in favor of paying the war debts. He also favored protective tariffs to shelter the developing industries, and a strong federal government including a central bank.