The way I've put it in conversation is this: while the equalization will balance out in many ways, pulling "third-world" countries up closer to "first-world" standards of living, the reality is it is highly likely that first-world standards will actually decrease... for the first time in quite a long time. Now, one can argue this is a good thing because we first-worlders are overconsumers, polluters, and many other reasons, but I don't think it's fair to hate on people wanting to protect their own standard of living.
I have theorized, perhaps wrongly, that this is part of the real, behind closed doors, push for brexit in the UK, especially seeing as currency is the great entangler and now that Europe are all on the Euro, the UK wants to get out before the Euro starts having major issues, and they probably saw that coming which is why they never left the pound. So ignoring the more unsavory reasons being touted for brexit, I think it shows a certain amount of people intuitively understand globalism might reduce their standard of living which is why we are seeing an increase in protectionism in much of the first-world.
Note: I hate the terms first-world and third-world... any better suggestions on that are welcome.
you want "developed" and "developing."
There are models where you could still have uplift without those issues but they are not what we are doing.
Our trade deals exclude environmental, labour, and other non-goods protections. So As a result we end up with the race to the bottom that you mentioned.
The fix is trade agreements that enshrine protections for more than just the goods being produced.
China is going to destroy their environment with or without incoming US capital. They will also continue to employ children, etc.
Globalization puts more demand on their system so their people get higher wages, better conditions, cleaner work environments, etc.
Competition for their labor pool and their environment in general means they don’t have to give it up under bad terms.
The problem your math teacher has is that there are significantly more people qualified and willing to teach math at that level than there are people qualified to do your job.