I know in Australia that CASA requires all student pilots to have (or even demonstrate) a good command of the english language.
yet even down under, where we all speek 'oztroin', & are statistically probably the least likely to learn a second language (beyond our version of 'english') we are also trained to use "MAYDAY-MAYDAY-MAYDAY" to prefix our distress messages & "PANPAN-PANPAN-PANPAN" for urgency messages.
seems good enough for everyone else.....? who not the U.S. too?