That's one guy's opinion. He says NAFTA created a race to the bottom, but any competitive free enterprise system can be viewed as a race to the bottom. Adam Smith's "The Wealth of Nations" is the granddaddy of all economics texts, and what he wrote 240 years ago is still true: economies are less efficient when disrupted by monopolies and special interest lobby groups. Putting tariffs on certain imports is very much a special interest interference in the market. Let's take the lumber industry as an example.
US lumber mills fought for and won a countervailing duty on BC softwoods in the most recent softwood lumber war 2004-09, but ultimately it cost them dearly. The duty was repeatedly declared to be unwarranted (by WTO and NAFTA) and most of the monies collected were eventually returned to Canadian producers. In the meantime, mills on this side of the border consolidated locations and invested in ultra-modern equipment to push production costs as low as possible in order to survive; American owners preferred to take profits and for the most part did not modernise. When the duties came off, the American mills were completely exposed and there were numerous mill closures. Several of these were subsequently purchased by Canadian lumber companies (Canfor and West Fraser both now own more mills in the US than in Canada). Five years of profits didn't shelter those mills from their structurally uncompetitive position. There's an example of industry-driven tariff protection backfiring and having the opposite effect of that intended.
I support everyone's right to a decent job, and that means everyone on the planet. Is it wrong that Mexico now (finally) has a middle class because of the manufacturing plants that opened there since NAFTA? They still haven't seen the GDP and per-capita incomes they were promised going into NAFTA, but they've achieved a level of dignity that didn't exist a quarter of a century ago. Likewise for China, a couple of hundred million people there now have a living standard streets ahead of anything they could have hoped for 40 years ago. Why should middle class lifestyles be limited to just the wealthy white countries? Protecting "good jobs", I know what that means. It means using tax dollars and other government intervention so that dudes with barely a high school diploma can keep on tightening nuts at Ford or GM or Chrysler for $120K a year. It's patently unsustainable, but no one wants to admit it because it's 'unpatriotic', not to mention virtual suicide if you're a politician. But when we take the nationalist rhetoric out of the equation, what we are seeing is a slow spread of wealth across the planet. It's far from equitable, but it's a start.
Henry Ford paid his production line workers more than the normal semi-skilled wages of the day because he needed to create a class of people who could afford to buy his products. He had a car at a price point lower than anyone else, but still very few people could afford to buy their own car. That is no longer applicable in north america, but very true in many other regions of the globe. The growing middle classes in China, Brazil, Korea and Mexico now have real buying power. There are huge trade opportunities for developed economies, but the jobs produced won't look like the "good jobs" of old. The world owes no one a living, if things are changing and your livelihood is under threat, then take steps to protect it. Education, re-certification, relocation, downsizing, whatever it takes. We humans are the product of evolution and as such we need to keep evolving. Fighting these massive global forces is pointless. Instead of focusing on the flaws in TPP and NAFTA, work on keeping your job/business and your family secure and provided for.