Still they will be right to do it.
I think speaking English is sign of british colonization, and it is nothing to be proud of.
Speaking Spanish (in Spain), Italian, Portuguese, French, and other
Romance languages are a sign of ROMAN colonization?
There is a lot of people speaking one language for colonization reasons (becoming its natural/born language after time), and there is a lot of people speaking English like international language, as "lingua franca", no as born language.
I don't like English (because I hate they write different they speak, its like learning 2 different languages), and I think it would be much better to use a standard, regular and artificial language (for example Lojban) for tha international use, but obiously English is actual and only "lingua franca" and you must know it if you want to communicate with most world or simply read about something advanced or not too much common (at some level most knowledge is found in English and not in other languages).
PD: Of course, British colonization was not like Roman or Spanish empires, but that is another (and controversial) history.