It is difficult to answer that without risking to be censored for talking politics in the Lounge.
I will risk it anyway: Lots of USanians blindly accept The Leader's claim that the nation is the world's leading nation in corona testing. The leader tells them, so why should they care to check e.g. the worldometers.info survey showing that in tests per capita, the US was earlier today ranking #43 on the list when ordered by tests per capita? When their leader tells them the Truth, why doubt it? What is the use of checking false news resources?
The Great Leader condemns the Swedish approach of "let the virus spread!" - Sweden has currently 30% more deaths per capita than the US - The Gerat Leader praises the Norwegian approach, my country, with no mention that the US has six times as many deaths per capita as Norway. Which True American looks beyond The Leader and his claims? Maybe a small handful of journalists, but they are easily knocked down for asking "nasty questions" at the press conferences.
I wish that this was limited to The Great Leader, but I know it isn't. To take one example: I was living in a US family for a year. Sometimes they bought loaves of bread from a baker using bread bags printed with "Bread for the world" (g** knows why!) and a series of different flags. For the flag labeled "Norway", the red and blue colors were interchanged. I pointed that out to my host family. They hardly cared to shrug: So what? The baker couldn't know that someone knowing the Norwegian flag would see those bread bags!
Another example, although second-hand: A colleague of mine told that he had been working with a US colleague at IBM (tradtionally more multi-culturally oriented than many other companies), complaining about poor support for the extra Scandinavian letters, æøå or in the Swedish variants äöå. This US guy, working with internationalization, claimed that they had full support. When my colleague asked about these letters, the issue was completely unknown to the US guy - at first he refused to accept that there could be other letters than a-z!
Lots of web stores insist that there must be a "state" level between the nation and town level, because that is the way it is in the US. In the phone number, they insist that there must be an area code between the nation code and the local number, the way it is in the US. They insist on a zip code following the state abbreviation, because that is the way it is in the US. How could anyone ever expect anything else? So non-USanians must fake it by repating the town name in the "state" field, and repeating the zip code in its proper postion as well as where the web page or application demands it, in the US of A defined position.
Lots of software take for granted that the full stop is a decimal separator and the comma is the thousands separator. Why would anyone ever think of doing it differently? Clock is by AM/PM - anything else is for the military guys, isn't it? Why would anyone ever consider a date format different from "May 12th, 2020" - anything else is outright silly, isn't it?
From my very first stay in a US family, in high school age, and onwards, I have countless times had to "defend myself" agaist the sometimes intense interrogation: You are not serious, are you? Claiming that you would not want to move to the US of A if you had the opportunity to? Why don't you apply - with your education, you would be accepted immediately! I have spent enormous amonts of energy on explaining that there are values in society, people, environment ... everything! that are not valued in an US society, but valued by me. It is not at all understood by those US citizens I have met. The count is quite high.
Let me conclude with an example from Norway:
One of my coworkers were born grew up in the US of A, and came to Norway as an adult. She quickly adapted to our morals. When her sister was visiting, seeing the two daughters of my coworker playing on the lawn, two and four years old and stark naked, she went straight out to buy binkins for those little girls "to cover their bodies".
Nowadays, even National Geographic goes to extremes to protect sensistive American souls from the shocking fact that in other parts of the world, girl kids (and boys, too!) of two and four years do run around stark naked. That is perfectly fine! Why not? Even taking photos of them is perfectly fine - but of course we cannot show them on internet, in case some super-sensitive US soul might technically have access to them. So we must keep those photos under strict control so that they do not offend those tender US souls...
I sometimes get a feeling that USAnians honestly believe that naked bodies are so unnatural that they nowhere in the world are acceptable, regardless of culture, age and sex. It cannot be possible that any human, anywhere in the world, do not develop a modesty, a shame, from age two at the latest. We do in the US of A, so that must be the natural thing! And don't tell us that we have enforced our morals on the kid - we have been perfectly neutral and open! It comes naturally!
From having lived in a US family for one year, later for eight months as a student, and later on about a dozen professional travels, I have a strong impression that fd9750 is right: The awareness of anything outside the US of A is geneally very low. Even for those knowing that there is something out there, the importamce of the US of A is frequently grossly over-estimated.
USAnians seem to think that they represent The Strong and Rightous Father, Leading the World ... while the outerworld sees US of A as one of the world's countries. Currently it is better at destructing non-Western civilisations than any other country, but in European countries there is an opposition questioning the virtue of that capability. The US doctrine is essentially "Peace is enforced by destruction of cultures different from our own". Not all Europeans subscribe to that.
Bottom line: ZurdoDev's claim that most of the US of A population "is hardly aware that there is something like a world outside of the USA" should be modified to "is hardly aware that there is anything outside of the USA, either in a geographical or cultural sense, that is valuable and worthy of protection, even it it conflicts witn the culture or ideals promoted in the US of A".