What will happen if all UN Nations do away with visa formalities as was the case in the historical past?

In the past in history there was no visa requirements to travel from one country to another.People moved about freely and the visitors were welcome in many lands except of course if they were colonists.For example the famous travellers like Fa Hsien,Vasco de Gama,Ibn Batuta,Columbus etc did not have visas for the countries they visited.


What if all the nations of the UN agree to implement this past practice,what will be the likely outcome in the world.|||civilisations should move forward not backwards.|||Well, among other things, you'd have massive migration. Which would lead to complete and total chaos, as hundreds of millions of people from the Third World would attempt to enter the U.S., Canada, Europe, Australia, and a few others. The health care systems of these countries would break down, unable to cope with such high numbers of people who, for the first time in their lives, have access to anything like decent medicine. There'd be housing shortages, and food distribution would have to be completely refigured.





Also, global organized crime and terrorism would flourish, as would racial tension.





These are just the things off the top of my head -- there might be some good things, too -- maybe increased cultural exchange, maybe some goods would be cheaper.





I'm sorry, but the examples you're holding up from hundreds of years ago, with expensive, arduous travel made by military and cultural elites, in a world with likely 100-200 million people total, just can't be compared to today. Realistically, the Third World has everything to gain from this type of agreement, and other countries would be utterly ruined, so I don't see it happening until a great many other things change in the world.





Sorry to poop on your parade, it's a nice idea!