Can I just say before I start that Not so bright, is appearing to be the brightest person here so far, me excluded of course(no arrogance intended). Please dont attack me but rather the argument if you can, as your opening is Ad Hominem and doesnt further your argument.
imports dont have to be of higher quality. They are often of much lower quality than local products, and occasionally of equal quality. Merely look at imports from China in Australia. There products are generally terrible, and fall apart much quicker than local products but they are imported due to there lower price anyway, as for example a worker in the West may get $20 for each completed clothing item of high quality and a Chinese person may get the equivalent of 2 cents for each poor clothing item and that is why despite travelling costs and tariffs they are still available in the West. The same is true of meat and livestock.
In your second paragraph you ambiguously refer to nations, in a theoretical sense, however this is a terrible mistake. You can only refer to current nations to prove your argument here, as in theory much of what your saying is complete nonsense. A nation with a highly skilled and highly paid workforce is of course going to be able to compete in the more labour intensive industries as well, as there will always be a lower part of the working force, proletarians, that cant particpate in skilled work. they can make far better quality products thus satisfying consumer utility to a greater extent then imports do. the nation will not suffer from this investment either as it provides jobs, thus income, thus increased consumer spending through increased purchasing power, thus increased economic growth. Once again i refer you to John K. Galbraith who admired the Nazi's for their economic ability, and this is what they did.
No country can produce everything it needs at the best and most efficient price in the world. You are once again refering to theory here which isnt correct, you need to specify current countries, as in theory one counrty could occupy the majority of the world's surface etc. and thus produce everything at the best prices. All countries benefit from trade, which is whole point in the very existance of the capitalist market system. Again theoretically they dont, some nations trade "gold for bronze" and dont benefit at all economically but must due to other reasons. The point of the capitalist free market system is not to exist for trade. It exists for private ownership, entrepreneur's, consumer sovereignty etc. and it benfits the aristocracy and Bourgeoisie the most with the proletarians achieving some benefit as well.
Of course we dont just look at volumes but at there relative prices when exporting and importing. Making more money for the American shareholders does not neccessarily benefit the nation. As providing the jobs at home leads to increased employment, increased income for the particular population, increased spending, increased taxes, and increased economic growth. That benefits the nation far more, once again this was the Nazi ideology and the theory used to escape the depression by particular nations.