Not sure quite what the rules are in other countries and other states, but to properly graduate high school in Florida with all the right credits to go to university, you need to take a foreign language. This would typically be Spanish. But depending on the school, other options may be available (at my school, French and, for a little while, Japanese).
But I think the big problem in the English-speaking world is not the lack of mandatory languages, or the almost intentional ignorance that I feel like many people perceive [from Americans, at least]. Rather, it’s just not all that necessary, pragmatically speaking.
I am Arab, I grew up in the U.S., I went to university in Russia, and my roommates were from China. I feel like all four groups have similar reasons for their difficulties with other languages.
While, of course, learning any language is useful, and there’s always something interesting that you would miss out on otherwise, there is such an absurd amount of stuff available in English. And so many people you can communicate with purely through English. For better or for worse, it’s not quite like being from Iceland or Estonia, where the total number of people you can communicate with in your native tongue is fewer than the population of Chicago.
When I think about my friends who are shockingly good at English, the people who not only understand the rules well but also the culture and could pass as a native speaker, at least over text, they are people who had a serious motivation to learn—like my friends from Lithuania who grew up on English-only games, like RuneScape, as kids and needed to have some ability to speak if they wanted to play.
If anything, I’m less surprised that English speakers tend to be so not-fluent than I am that Chinese speakers are as “fluent” as they are.