While there are a thousand different reasons why people migrate to the U.S, there are some major ones that we can cover.
<u><em>War.</em></u> War is a major one that sometimes <em>forces</em> people to move to the U.S and other countries, being a haven that will protect them from all the dangers.
<u><em>College.</em></u> Pretty straightforward, people come to better and further their education.
<u><em>Jobs. </em></u> Also pretty straightforward, people come to work here, to live here, the job opportunities are close to endless.
<u><em>Family and friends.</em></u> Having family members or close friends in the U.S often is a factor for people moving to the U.S.
They often gain more freedoms* than they have had in their previous country, a democratic country with personal choices like I mentioned earlier, more job opportunities*, and some of the world's most elite colleges are here. Some of the downsides of moving away from their birthplace and moving to the U.S is that there is a very real possibility of moving away from family and friends, and essentially starting life over again.
The original purpose of the publication of essays contained in the Federalist Papers was to convince the states and people to ratify the Constitution of the United States.