I do think that imigrants should be allowed to enter the US because This is a free country.
Impossible to answer. Some countries such as the US have immigration quota's, some do not. This means that there is no fixed amount of immigrants moving to new countries each year.
Chinese
National origins act
Japan
I think that Chinese people were not allowed to become US citizens.
Mexicans
One factor that drew many immigrants to the U.S. and allowed people to prosper by relying on their own resources was the type of government the U.S. has. In a democratic society the people are free to choose their career. Many immigrants also came because America was considered to be the "promised land".
Approximately 1.3 million immigrants are admitted into the U.S each year.
Chinese laborers
The Naturalization Law of 1790
According to the 2009 United States census, there are over 36 million immigrants here in the United States. The immigrants are not solely composed of one race, but are composed of all the races and include legal aswell as illegal immigrants.