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
Lincoln did not see a tariff as a tax on low-income Americans because it would only burden the consumer according to the amount the consumer consumed.
By the tariff system, the whole revenue is paid by the consumers of foreign goods… the burthen of revenue falls almost entirely on the wealthy and luxurious few, while the substantial and laboring many who live at home, and upon home products, go entirely free.