You cannot change your skin color, you can change your citizenship though. And it's not just America, you'll run into these restrictions in every country, often times more strict.
> You cannot change your skin color, you can change your citizenship though.
Not on your own. You need to find a country willing to accept you as a citizen. For the vast majority of people in the world, the only countries that would accept them are those where they would be worse off. So the countries that do (successfully) prioritize prosperity of their citizens also effectively lock out most people from elsewhere. The trickle of immigration is just that, a trickle - it is deliberately constrained with various rules and requirements, and it would be a much bigger stream if anyone who wanted to change their citizenship could apply (even if you filtered out, say, people with criminal records and such).
Can you elaborate on why you think that isn't true?
Imagine I'm a cab driver in Pakistan and want to become a cab driver in the US. Can you point me to what form I would fill out in order to apply for a visa?
Not on your own. You need to find a country willing to accept you as a citizen. For the vast majority of people in the world, the only countries that would accept them are those where they would be worse off. So the countries that do (successfully) prioritize prosperity of their citizens also effectively lock out most people from elsewhere. The trickle of immigration is just that, a trickle - it is deliberately constrained with various rules and requirements, and it would be a much bigger stream if anyone who wanted to change their citizenship could apply (even if you filtered out, say, people with criminal records and such).