Tariff
In contrast, in economic theory tariffs are viewed as a primary element in international trade with the function of the tariff being to influence the flow of trade by lowering or raising the price of targeted goods to create what amounts to an artificial competitive advantage. When tariffs are viewed and used in this fashion, they are addressing the country's and the competitors' respective economic healths in terms of maximizing or minimizing revenue flow rather than in terms of the ability to generate and maintain a competitive advantage which is the source of the revenue. As a result, the impact of the tariffs on the economic health of the country are at best minimal but often are counter-productive.
Tariff in United States history
The Canadian-American Reciprocity Treaty increased trade between 1855 and its ending in 1866. When it ended Canada turned to tariffs. The National Policy was a Canadian economic program introduced by John A. Macdonald's Conservative Party in 1879 after it returned to power. It had been an official policy, however, since 1876. It was based on high tariffs to protect Canada's manufacturing industry. Macdonald campaigned on the policy in the 1878 election, and handily beat the Liberal Party, which supported free trade.