The USA handles this is the same way almost every other nation on the planet does....
If you want to visit the USA (for whatever purpose), visit the US Embassy or Consulate in your country and apply. Such applications are handled FIRST and as quickly as possible.
If you want asylum, the process is the same BUT because refuges often have left their country and because the US may not have an embassy in that oppressive country, such may go to any embassy or consulate (such as a neighboring nation) and if one is not abilable there, they can go to a UK embassy or consulate (they are in more countries than US ones) and apply there. Such applications are handled FIRST and as quickly as possible.
The USA has accepted more such application than any other country... there are CURRENTLY about 37 million LEGAL immigrants and refuges in the USA - considerably more than the entire human population of Australia.
Until the 1950's, the USA permitted people to just show up and they would be vetted at that time. Many of these were at Ellis Island (I've been there, done the tour). This was ended because it is inhumane - some of these people spent all the money they had to get to the USA and then were turned back, a very difficult thing! So the USA ended this practice of handling applications HERE - we did this long after most countries came to the same conclusion and also ended it. So for 60 years, the USA has done this like almost every other nation. It not only allows things to be done in an orderly and more complete manner, but also in a more humane manner - not separating people or sending people back home when they have no means to go home. People can KNOW they can enter easily and legally BEFORE they sell things and arrive on our shores. A much more just and humane process....
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