this page is not about demonyms

So what? Do you think that proves that America doesn’t often refer to the USA? Do you think that the way some people speak Spanish determines how English is spoken?

It is not about the English language. It is about ignorance and a culture of complacency.

the fact that spanish was spoken in usa before english has nothing to do with this website

In the first article, he conclusively affirms that what was founded on July 4, 1776 was not one country but several, countries (states) that were organized together to confront and preserve their recent freedom against the all-powerful Great Britain, and that it is this is the reason for the "strange" name, the consideration of American countries ("American" because they belonged to the continent called America) called "The United States of America".

This is why in the declaration of independence the word "united" appears without an initial capital letter and after mentioning the number of states but the words "states" and "America": "the thirteen United States of America", and why the assembly that declared this independence was called "Continental Congress" or because its liberating armed force was called "Continental Army", or that in the Articles of Confederation it is written "the name of this CONFEDERATION shall be The United States of America" and not " the name of this NATION", etc etc.

Then -almost a hundred years after independence- the need would come to consider one nation and not several (consequence of the civil war) and this would be done through the use of the word with which they felt most UNIFIED, New Yorkers, Virginians , Pennsylvanians, etc against the British enemy, "Americans", a word that in the first decades of the United States was used only in its continental sense by the inhabitants of the new countries/states.

https://pintsofhistory.com/2014/10/23/why-the-u-s-has-no-name/

https://ejournals.library.vanderbilt.edu/index.php/ameriquests/article/view/15/24

Glad you shared this important info with us. Some people here might have never had a proper instruction on how the U.S. was started and why. And as you put it so eloquently, there are people who will not get it. I said this and some refute it but as you have shown us a little bit of research and history lesson shows us that the U.S. was a unity of sovereign States or nations which got united to be stronger against the intrusions of any other nation and usually from Europe which is the continent these States were trying to get their independence from. Thus, the United States, formed in the continent of America and thus they included it on their name of this Federation/Union, The United States of America. Not that America is the country, no, America is the continent in which these United States were founded.

Correction: "the thirdteen united States of America"

thank you Mrs. Anonymous! And what do you think about using the word "American" as a nationality?

Fabian, Americans are all those who live in the continent of America.

Uruguay is also in America

OP didn't say it wasn't

But in other cases those same words are considered only formal clarifications about the type of political order by which that country is organized, such as "República Argentina" (whose central denomination is "Argentina"), State of Japan and United Mexican States. (institutional name that Mexicans hardly use in their daily lives, only in bureaucratic legal matters, for them their country is basically called Mexico).

It doesn't seem so serious to me that the United States of America is sometimes abbreviated "America", because it is the informal way of doing it, the official way is "United States". What does seem debatable to me is his nationality, "American"; but anyway I think it would be fixed just by adding "US", that is "US American".

America means the continent how can calling the U.S. as "America" be something of an informal name of that country if it was added due to the fact that the United States were founded in the continent of America? Let's see, if let's say a country appears and wants to be called "The United Provinces of Africa" and then people would then be lazy and just "informally" start calling it "Africa". Wouldn't that be a conflict with the continent of Africa? Well, how about the real country of "South Africa" do they say they are just Africans? If they do then they are correct because they are in that continent, but they usually say they are from South Africa. So it is the same with the case of the U.S., where they decided to put the continent's name in their name to denote where the U.S. is located and in what continent which is "America".