Why do many people from the US call themselves americans as if they where the only ones in the continent?

Americans are all who where born in North, Central and South America. So, why do many people from the United States use the word American only for themselves. Examples:

In sports: American League of Professional Baseball Clubs, American Football League, All-America Football Conference, American Basketball Association, League of American Bicyclists, etc. How could these leagues be american if they only include teams form one country?????



In the educational system you can find American History or American Literature but they only focus on history and literature from the U.S.



In news agencies such as CNN you can find spaces like American Economy, American Road Trips, etc. But they all refer oly to the U.S.



And of course, when you ask someone from the United States "where are you from" ? you will get the answer: AMERICA. If you ask for the nationality you will hear AMERICAN... Why is this???? Is it a matter of not knowing geography, lack of awareness in continental and global issues??? or what??

Why do many people from the US call themselves americans as if they where the only ones in the continent?
Well of course they believe that they are the most important country in all of North or South America and that the rest don't really matter so they take the word America for themselves. Come to think of it what should the correct term be for a citizen of the United States of America ? Would it be a "United States of American" , rather clumsy don't you think and so it is shortened to American. Anyway Canadians and Mexicans and Brasilians and the rest are very happy not to be called Americans