One who is born in the United States of America is defined as a United Statesmen, just as one who is born in Canada a Canadian and one who is born in Mexico is a Mexican. All Canadian, Mexican and a United Statesmen can be called Americans.
1) A person born in any of the 50 states of the United States of America is a United Statesmen.
2) A person born in Canada is not a United Statesmen.
3) A person born in Mexico is not a United Statesmen.
4) An American can be Canadian, Mexican, or United Statesmen.
5) A United Statesmen is specific to its region of North America.