It is because of government policy that we speak English
as our common medium, nothing much to do with racial mix. Why
you don't see Malaysians speaking English as the common medium,
that is also due to their government policy.
If a Singaporean chinese think that Mandarin is too difficult for
him to learn, then he is not fit to be chinese. It is his mother
tongue afterall.
Mandarin is whose mother tongue?
If a Chinese mother speaks Hokkien, or Cantonese, or
TeowChew, what is the mother tongue of the children.
What if the government decrees that Cantonese should be the
language of the Chinese. The Hokkien, Hainanese, Teowchew, who then
can't speak Cantonese are not fit to be Chinese?
Lee Kuan Yew was asked why not Cantonese, when the government
embarked on the Speak Mandarin campaign. His reply was: Yes if it
will be, if Cantonese, or Hokkien is the main stream language.
So Mandarin is actually a chosen language, it is the language of
the elite of ancient China, imposed on the minority, whose freedom
to practice their own culture is "guaranteed" by the
politicians.