I disagree.A government that opens the borders WIDE and not only allows them in, but doesn’t give a damn about the invaders having Covid, TB (the harder to kill kind) , and Leprosy is a government that doesn’t give a single thought to the wellbeing of the country they are supposed to represent! Period. Anyone denying that isn’t happening needs to start digging their own grave now.
Up until the early 1900s, there were little or no barriers between countries to people movement.
There was the occasional hinderance of a specific nationality entering a specific country (e.g. keeping Chinese out of the US), but it was not "the norm".
Granted, more movement is possible due to advances in technology, e.g. air travel.
But, I suggest the bigger issue is what motivates people to move. I suggest it is two things, both of which have increased immensely in the last century:
A. the rise in government supplied services: free education, welfare, old age pensions. This motivates people to go somewhere to get something for nothing.
B. the rise of intentional destabilization of vast areas of the planet: standard US government policy, especially for the Middle East, North Africa, Latin America and South East Asia.
Reduce these two, and emigration/immigration will vastly reduce. Or at least those who do are more likely to be assets to their new countries of residence than liabilities.
One could also ask whether a government such as the US, where almost the entirety of the populace are either immigrants or descendants from immigrants, has the moral right to prevent others from immigrating (unless their sickness is contagious or they are arch-criminals).
Of course, it is not practical with all the FREE STUFF the US governments (of all levels) give away . . . but that is another topic.