It is fair to say that English-speaking Americans are very resistant to becoming bilingual. Many citizens of other countries speak several languages fluently. It is important for them to be able to speak to people from other countries. Many Americans, however, are not even exposed to other languages until later in school when it is harder to adopt a second language.
Americans tend to have an arrogance of superiority over other people because most believe that everyone wants to live in America. Americans can often be true nationalist holding hostage to its heritage of freedom. There are many more people in the world who are taught multiple languages at a young age. American children are typically taught English until elementary school.
Yes, Americans know that their country is the world leader so they think they don't have to learn other languages. They are stuck up and think that all others should learn to communicate with them or America will have no business speaking with them. It is in the other country's benefit to conform to America.
Americans are the most resistant in the world to becoming bilingual speakers. I think that Americans are not exposed enough to other languages because it is not really pushed in our school systems. English is worldwide in all countries and most everywhere you go you will find someone that speaks it.
The vast majority of Americans I met actually seem to want to learn Spanish, because it is quickly become wide spread in the country. Of course there are many who are opposed to other languages, but I do not think we are the most resistant to it. It's just that everyone knows English.