The largest problems with people who are against NAFTA

The TPP is not free trade, it is managed trade that is only designed to expand copyright law until nothing is in the public domain. I do not support the TPP and this post should not be construed as that I support that incredibly destructive economic plan that is being proposed currently because it will damage our economy by restricting copyright and restricting creativity.

The biggest problem with people who are opposed to Free Trade is the arguments they make. First of all they don't see free trade as an opportunity to subsidize goods made in nations that respect people and want to close our borders completely. In Europe we see the consequence of lack of free trade with the US in their dependency on Russian natural gas and oil, which is causing major international relations problems currently in that they have no reaction to Putin's latest actions in Ukraine. The lack of free trade in oil and natural gas in a US/Canada/EU trade bloc hurts average Europeans and the economy of the EU every single day.
Second, their arguments tend to be fallacious. One argument I have honestly read in my international relations textbook from the anti-globalization people is how opening free trade with Mexico caused an increase in direct imports from China. This is ridiculous because it didn't change our relationship with China. We still pay the tariff for all of the Chinese goods, but these two events happened simutaneously and opening our border with Mexico had no effect on the taxes on Chinese imports.
Third, they support dictatorships by not opening the borders for people from those countries to visit the US, Canada, Australia, Japan, and EU. We do have more freedoms than Middle Eastern nations, China, and Russia. If we open the borders to allow more tourists and students to visit us from these countries they will choose our liberties over their regimes and it will help overthrow these entrenched dictatorships and move them towards a more stable democracy. By keeping high barriers to tourism from these countries it further alienates them and increases the power of their internet censorship complexes. In short, visas for people from unfree nations support the dictatorships.
Fourth, when I read arguments from prominent tariff supporters they tend to get their basic facts wrong, which makes me discount most of their arguments through lack of trust and makes me a centrist on this issue. I am still waiting after doing a lot of reading on this issue for a well-researched argument based on data that convinces me that tariffs are good for the global economy and freedom. I have never found one.

For this reason I am in favor of free trade between nations of good human rights values to start because there is absolutely no reason to not have those rights. The US and EU represent over 30% of global economic output together, which means we have an incredible amount of economic power over poorer nations to encourage them to develop their human rights. Free trade should be seen as a way to increase freedom because there is no evidence that it hurts the average person in general, and in fact there is plentiful evidence that average people benefit when foreign firms come in on the average, which means you must remember that there will be in large samples a bell shaped curve with the anecdotes on the left and right giving the nuggets that extremists will latch on to.