Why exactly is America giving people greencards?

Question

what are the benefits to the americans?

Answer 1

to keep track of non citizens who come to work or live in our country.  its the legal way

Answer 2

Then you get a bunch of people who think they are lucky to have a green card so they work like h**l for a few years then they visit home and realise even though their families make much less then they do they have a much better quality of life.

Answer 3

because bluecards would be less fashion forward.  

Answer 4

so they can get into the US?

Answer 5

They give greencards to spouses and family members of American Citzens first and foremost.  They also give greencards out to citzens of other countries which are not represented very well in the USA e.g. Australians or certain african nations.  

The benefit to America is that it gets to keep its long standing tradition of cultural diversity.  The USA was built by immigrants and they want to keep that tradition going.  Mostly all developed countries have a similar system.