We begin at looking at the keyboard layouts. If C++ was designed in English, how does someone without an English keyboard program in an English language? Well the answer is, all keyboards are English.
As you can see, the French keyboard layout contains all the letters in the English alphabet (although the layout is not QWERTY like we're used to). Despite having to accommodate additional special characters, the ability to program in English exists. But what about something more obscure like Japanese?