In addition to tariffs as taxes, quotas and tax-free shopping may be considered as another type of tariff with more subtle effects. The goal is to create artificial scarcity and drive the price of the foreign product upward to advantage the domestic producers.and
Why do we use tariffs?
Tariffs are a political device that artificially restricts the importation of goods purchased from foreign (non-domestic) producers with the goal of making these goods less price-attractive to corporations and consumers to convey an advantage o the domestic producer. This advantage can be neutral to achieve equivalence with foreign pricing or advantageous to convey supremacy to the domestic producer.
One, tariffs are imposed nationally or internationally to regulate trade so that one party cannot exert systemic supremacy over another.
Two, tariffs are imposed to redress currency manipulation where one nation maintains an artificially low currency conversion rate to encourage consumers and corporations to buy goods which appear cheaper than those offered domestically.
Three, tariffs might be imposed to redress the systemic institutional theft of intellectual property which allows manufacturers to avoid the tremendous costs of research and development and pass the cost savings along to consumers as lower prices.
Some examples:
A primary example would be goods manufactured in a nation with low labor costs and sold for at a lower price in a nation with higher labor costs. Since the higher-cost producer cannot effectively compete in the marketplace, they are forced to innovate new products, reduce their labor costs through automation, expert systems, and robotics; outsource production; or go out of business.
Another example would be a nation subsidizing some portion of manufacturing, labor, or currency translation costs of a manufacturer which allows the manufacturer to dump their goods in another nation at a substantially lower price, thus forcing domestic producers to take affirmative action to remain competitive.
Sometimes domestic tariffs are used to protect obsolete and failing business models from legitimate competition. Hence we see commodity goods such as telephone and cable services being sold at premium prices by deliberately designed complexity which creates confusion in the packaging (bundling) of services which permits higher prices.
And, then there is the government's desire to impose taxes on the population in such a manner as to hide them from those taxed. If the government did not collect these taxes in small increments in utility taxes, at the gas pump, or embedded in large luxury purchases, and presented a tax bill at the end of the year -- the populace would revolt and throw most of the politicians out of office.
The current situation.
There is no doubt in my mind that China is a low-cost labor source, having a 900 million person workforce (compared with approximately 140 million in the United States)that works at what Americans might consider slave-labor wages.
There is no doubt in my mind that China manipulates their currency to ensure that Chinese purchases are cheaper than their corresponding American counterparts.
There is no doubt in my mind that China engages in both governmental and commercial espionage to gain an unfair advantage for their military and commercial ventures.
The possibilities of a trade war?
If one nation retaliates against another, it is most likely the response will be tariffs imposed on that nation's goods; resulting in a death-spiral of tariffs and quotas that may benefit domestic producers in the short- and medium-term, but may be overly oppressive to the consumer who may shop in big-box stores like Walmart, Costco, etc. and have come to rely on lower prices.
Who is hurt?
While the case is made that domestic producers (and their employees) benefit from tariffs and quotas, it is the end consumer that always pays the price. With a disproportionate impact on the poor who have managed their meager budgets using the lower costs goods available in the marketplace.
The Retail Council of Canada claims that an increase in the duty-free allowance for cross-border shopping from $20 to $800 would lead to hundreds of thousands of job losses and cut billions of dollars from the Canadian economy. In this case, common sense reveals that is not so much about jobs since most of the purchases come from sources in the United States, but a loss of tax revenue for a cash-strapped government. <Source>