I think what some people need to realise is that a tax on imports (or, any form of protectionism), roughly equal to a tax on exports.
When an American buys goods from China, they want to spend in dollars, but the Chinese firms want to be paid in yuan. Therefore, a conversion takes place: at some point during the trade, X amount of dollars need to be traded in for the return of the equivalent amount of yuan.
Now, here's the important part: the people out there, who run the exchanges do so because they know that the dollar holds value. Why would a Chinese currency converter want to hold dollars, when everything they could want to buy from China has to be paid for in yuan? How would somebody benefit from giving over yuan in return for a dollar that they cannot use? Simply, they wouldn't, and the exchange would never happen, and international trade could never work.
The currency converters like the dollars, and they hold onto the dollars because they know that in the future, Chinese people will be wanting to come along and buy the dollars for yuan so that they can then buy imports in from the USA. As such, it is always true that imports = exports.
It is basic theory that current account deficits and surpluses are only a short term consequence, in the long term, all current accounts will tend back towards marginal deficits/surpluses. The reason for the huge imbalances currently is simply down to the huge imbalances in economic development - as China's economy catches and surpasses that of the USA's, the importing/exporting habits of the two nations will reverse, and trade will balance.
Given that any kind of protectionism, as Killiana1a is advocating, will stand to reduce the level of imports now, it only stands to reason that it will reduce exports in the future. With both a reduction in imports and exports, nothing is achieved, and all this results in is a reduction in economic activity all around the world.
Protectionism is, ultimately, bad for everybody, including those who are protected (and, of course, this doesn't even get into other arguments about protectionism to do with enhances alliances around the globe, reducing conflicts, and other basic economic principles such as enhanced competition, greater markets, and greater economies of scale).
