C J Campbell writes:

The Chinese are studying English by the millions.

So that would come out to, what, 0.4%?

People can study a language for years without learning it. It depends on
motivation, quality of education, and other factors. In much of the world
people study English for years but never become competent in the language. In
Europe, France has some of the worst English instruction, although all the
Latin countries of Europe are very poor in English.

It is a mistake to think that the things that are done on behalf of an
American cultural minority mean that America is going to change to
Spanish. Even less so for the entire rest of the world. English is
rapidly becoming the universal language of the world. Declare yourself
an English teacher and you can get a job practically anywhere in Asia,
the Middle East, Africa, or even South America.

Quite so. English is now favored simply because so many people already speak
it, and even two people who have different, non-English native languages will
generally choose to communicate in English rather than try to learn each
other's language. Spanish is mostly geographically limited to parts of the
Americas (keeping Brazil in mind), which does not make it useful in most of
the world.