Should it really be economic policy to fuck part of your own population so that another countries' migrants can make more money?

Dunno, when I did my econ degree economic development was still talked about. It seems that everyone has given up on economic development and would rather plunder a nation's workforce to benefit their own capitalist class.

Or would incentivize investing in said foreign countries with lower labor costs?

> If you have an ever wider empathic perspective, maybe immigration hurts poor Americans but helps poor foreigners even more.

This is actually a case of toxic empathy: that view isn't the one that leads to the best outcome, because it destroys your capacity to help for short term improvements, leading to long term negative outcomes and an increased number of victims. Tempering raw empathy with rational evaluation increases your capacity to help and leads to a greatly improved outcome.

To use a cliche: during a rescue, don't become a victim.

An overabundance of immigration disrupts the host culture, which is the feature of the world that is causing the good outcome -- that the host culture causes more human thriving than the culture being emigrated from. When you draw too much from the resources of healthy cultures to try and fix systemic problems in other cultures, you end up damaging the healthy cultures, not fixing the problem. This simply degrades the situation, whereas a slower rate of change would remain stable, and lead to a genuine improvement in the world.

It's a cancerous idea, caused by failing to regulate your emotions: you're not being genuinely empathetic, you're shirking responsibility to get high on good feelings because look at how woke.