A pure "free market" is impossible, it's a theory.
But the closer to the 'free market' ideal you can get, the better.
Y'see, free trade is a system. When countries pass laws that manipulate the market, there are costs. The 'invisible hand' will slap them.
When countries do pass rules that restrict or favor various market segments, they will pay a price for it. First, in bad choices by their govt, which will mean that their industries still can't compete, in the long run.
For example, I'd argue that this shift of low-skilled jobs off-shore is actually working in our best interest. We're going thru our pain early, and are being forced to find alternative employment/production.
Because the bottom line is this -- these jobs will be fully automated within a decade. These jobs will go away entirely. China will, within a relatively short time, find that they have invested heavily in a buggy-whip industry.
And when they're just beginning to deal with that, we'll have already moved on.