It also depends on taxes on earnings for foreign operations in the US and on the regulations tax structure of other nations.
Back to the proposed solution:
The fact of the matter is, the world is different than it was 40 years ago. Trying to bring back the old structure of regulation and taxation won't revive America and bring back glory days.
The lack of employment opportunities is a result of a lack of productive capital within the country. (which oddly enough, took a huge hit in the 70's when we all became Keynesians and starting inflating bubbles crazier than ever)
I will admit that allowing more free trade might be a contributing factor to the employment situation, but it doesn't even give half the picture. People are willing to work, and there is no way of employing them at a profitable rate. This means that there must be an inferior economic situation, which is most likely the result of the (tangible) capital makeup of the economy being inferior. Capital consumption and destruction happen during the economic boom and bust. To change regulation to employ them is to make them better off, and everyone else poorer. This is the cost of empire.