Tariff
A tariff is called an optimal tariff if it's set to maximize the welfare of the country imposing the tariff. It is a tariff derived by the intersection between the "trade indifference curve" of that country and the offer curve of another country. In this case, the welfare of the other country grows worse simultaneously, thus the policy is a kind of "beggar thy neighbor policy". If the offer curve of the other country is a line through the origin point, the original country is in the "condition of a small country", so any tariff worsens the welfare of the original country.
Presidency of George Washington
One of the most pressing issues facing the First Congress during its inaugural session was the issue of how to raise revenue for the federal government. Because direct taxes were politically unfeasible, Congress turned to the tariff as the main source of funding. The tariffs could also protect nascent American manufacturing by increasing the cost of imported goods, many of which came from Britain. Each region sought favorable terms for the duties on various goods. Because the federal government would be unable to even pay the salaries of its officials without passage of the bill, members of Congress were strongly motivated to reach a compromise. In July, Congress finally passed the Tariff of 1789, which Washington signed into law. The act created a uniform impost on goods carried by foreign ships, while also establishing a much smaller tax on goods carried by American-owned ships. The tariffs established by this and later acts would make up the vast majority of government revenue; more than 87 percent of the federal government's revenue between 1789 and 1800 came from import duties.