You have raised some points that other people have raised before. Let's look at them in detail.
Here is what actually happens when you tax the rich, in contrast to their threats:
https://www.theguardian.com/inequali...naires-threats
Personally, for the 2% of billionaires who do leave the country and set up "residence" in a tax haven, I'd propose a law stating that 100% of the income that they derive from activities in their original country would be taxed forever, no exceptions and no returns. If they want to benefit from a country's laws, then they need to pay for that country's infrastructure. I think such a law would be very popular.
I don't see GM moving their headquarters to China. Nor Microsoft, either. There is a reason that corporations incorporate in the US, and that reason is the stable laws that the US has. The fact that Apple has made Ireland a tax haven simply points out the fact that corporations normally act as sociopaths unless they are held accountable.
https://itep.org/fact-sheet-apple-and-tax-avoidance/ Personally, I think that denying Apple access to US markets would fix their tendency to benefit from US laws without actually having to pay for those benefits. Let them see how many iPhones they can sell in China.
Actually, having a "weaker" dollar does help most people in the US, because it means that US products are cheaper for the rest of the world to buy, and cheaper products means that more are sold, and more are produced and therefore more people are employed. It also makes Mercedes more expensive to buy, which means that a rich person might choose to buy a Tesla instead, thus employing Americans. When the money stays in the country, it circulates here, it doesn't go elsewhere where it acts as a claim against our future labor. "A foreigner with a paper dollar can tell an American, "By virtue of me having this dollar, you promised to work for me for a certain length of time, and I'll give you this piece of paper in exchange for your real labor. Lol."
As for Bernie's proposal to increase taxes on millionaires, here is an historical article about tax rates. Please read it carefully, because I discovered that when I started making more than the average income, I started acting like the guys described:
https://www.alternet.org/2008/11/why...id_high_taxes/
Incidentally, I pay as little tax as I legally can. I have a tax attorney and bookkeepers to ensure that I pay what I owe and not a cent more. In practical terms, this means that I can stack up dollars past what I need to survive and buy toys with them. If the personal tax rates were higher, I would avoid paying taxes by investing more in my business (since capital gains taxes would be lower in comparison). And so would everyone else. And I'm sure that you know, investment is the key to future earnings, assuming that you aren't paying politicians for favors, which can have much higher returns but is much worse for the country.