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.
Tariff in United States history
"I use no porter or cheese in my family, but such as is made in America," the inaugural President George Washington wrote, boasting that these domestic products are "of an excellent quality." One of the first acts of Congress Washington signed was a tariff among whose stated purpose was "the encouragement and protection of manufactures.".In his 1790 State of the Union Address, Washington justified his tariff policy for national security reasons: