[Luis Gonzalez]

"This does not take into consideration that since 1974, when so-called free trade began in the U. S., real wages stated to decline. Also, the rate of productivity stated to decline."

Free trade has existed since the inception of the Republic, protectionism and excessive tariffs were either the cause of the Great Depression, or made it worse, depending on which school of thought you believe, but you're welcome to prove me wrong, and welcomed to substantiate your claims.

Here's my shot: you're dead wrong.

[upcountryhorseman]

According to the Economic Report of the President, 1991; a chart showing Trade/GNP Ratio and National Productivity Growth indicates that, starting in 1973, productivity growth
declined as the trade/GNP ratio increased.

Real wages have declined because since 1973 we have converted to a service economy and lost manufacturing jobs:
manufacturing jobs paid more than service jobs, consequently, two-job households became necessary.