[throwaway2989]

There are plenty of Chinese diasporas all around the world. I'm willing to bet that if you asked around 20 people or so in an average American or British city you'd end up being understood in Chinese. Yet I don't see many people calling Chinese an international language.

It'll take more than just stats gleaned on wikipedia to make a coherent case. A large majority of mankind has no use for English and thus doesn't use it, and this can be readily witnessed firsthand by travelers who stray off tourist paths. (For instance I say rural Germany is rough going because I've been there and witnessed it firsthand.) That doesn't mean English isn't a lingua franca, it's just not the lingua franca in most of the world. In Latin America people will use Spanish or Portuguese, in Africa people will use French, Arabic, English or Swahili, in much of Central Asia people will use Russian. Even then, knowledge of those languages isn't a given.

The fact of the matter is that English isn't known or used by most of the world population. Arguing about the rest is just semantics.

[firatcan]

I am on you with this, sure English de facto language for many things. I don't believe it's just for business or research many things but most of rural areas or less educated areas all over the world has little amount of English speakers or even not at all.

For instance, let's take Spain or Italy not even Africa or Asia. I mean Europe, Spain, if you asked 20 people in Barcelona or Rome you'd end up being understood. On the other hand if you asked 20 people in Naples or Granada, the chances are they wouldn't understood you.