The Constitution grants to Congress the power to tax imported goods. In 1788, this was a major form of taxation. The federal government was not allowed to tax personal incomes. There was no Internal Revenue Service.
The government did tax imports that cross an American border from outside the nation. By restricting taxation primarily to tariffs, the Founding Fathers intended to keep the federal government income low, so that it could not significantly meddle in the lives of American citizens and would be less inclined toward war.
Taxes hurt. But at least this rule should surely be honored: Taxes should not be used to treat one group preferentially at the expense of other groups.
One problem with current taxes on imported goods is that the taxes are not applied uniformly. There is no flat tax on all imports. Congress has written in loopholes for special interests.
There are too many taxes. We need fewer taxes.
The federal government taxes personal incomes. It taxes corporate incomes. It taxes almost everything that moves. As a percentage of federal revenue, tariffs in 2010 produced about $25 billion, or only about 1% of total federal tax revenue.
A worse problem comes when the government passes import quotas. These produce no revenue for the government. These are favors to special-interest groups. The lobbyists make it worth a congressman's time -- money for re-election campaigns -- to write import quotas into laws. These are hidden from the public.
These quotas keep out goods. The public pays more for whatever they buy, but the money does not go directly to the federal government. It goes to the special interests who can sell their products at higher prices. It's a sweet deal.