Theoretical physicist here! (Disclaimer: PhD student, not professor)
One of my favorite things about theoretical physics is that it can be done almost anywhere. Here's what I need to do research:
- a reliable computer with reliable internet access
- access to research journals
- money to buy textbooks
- money to buy food, clothing, and shelter
- a desk, nice chair, and lots of coffee
- a Mathematica or MATLAB license is nice, too
These things can be found at any well-run university. So, in my opinion, the best place for theoretical physicists is "anywhere that pays you enough to survive and buy textbooks while providing enough free time to do research."
Obviously, wealthier countries tend to have more research universities, and it can be easier to get published if you're at a prestigious university. Still, the best journals care more about what your research says than where you wrote it. If you live in a safe area, your advisor is competent and helpful, and your university pays you enough, then you can do theoretical physics. That's just as true in Azerbaijan as in Zurich.
It's difficult to compare directly, but I've been to universities in the US and NL and the cost really is much
greater in the US than in the Netherlands. I think "10 times as high" is an OK first-order estimate. Undergrad tuition is misleading because many (most?) people don't pay the full advertised price. We submit our tax forms and financial papers to the university, they figure out what we can afford, then they charge more than that and we go into debt. (It's a special kind of debt which can't be discharged when you go bankrupt.) Then there's the health-system fiasco: my university requires me to pay $1200 per year for an insurance policy with a $50K cap. If I get seriously ill or hit by a bus, I'll go bankrupt.
For most science programs, grad school is cheaper. (Not for medical doctors!) Typically, we pay little or no tuition, work as teaching assistants, and get paid roughly the minimum amount necessary to survive. Many of us take on more debt as student loans.
Personally, I think charging people a zillion dollars for education - early in our careers, when we could be inventing things or starting businesses or starting a family - is one of the stupidest financial policies in the history of the United States. But I suppose that's off-topic for this thread.