Your history sucks. Mongolia was one country only when they
ruled china, and they extended the kingdom all the way to europe.
They were never independent countries. Vietnam was once ruled by
the french too, so?
China's map was first drawn in the 1800 during the qing dynasty,
and that included mongolia, tibet and manchuria which were
minorities region, and china was then ruled by the manchurians, a
minority. So which countries did China invaded and annexed? the
British just gave up their last colony in asia in 1997 and the
portugese in 1999.
do you know what Japan did before WW2, before you say that "The way
China is growing military and economically is akin to what Japan
was going through before WW2". Over the last 150 yrs China was
involved in its own civil wars, political turmoils, invaded by
foreign forces...is there anything in its history that make you
frightened of them, or it is because you don't know the history, or
they are taking your jobs?
Is there threat from China? yes, economically and culturally. All
the jobs will have to go to china because they are cheap and no
less inefficient. Why do we have to re-learn our mandarin,
unfortunately yes or our boss will send somebody to china.
So how? switch focus and imagine they are military threats in the
future, on the basis that "how can you be sure that they won't"?
build up your military arsenal in case a war starts? do we stand a
chance? if china does intend on destabilizing any local government,
they just do what the religious extremists do and plant bombs. If
that happens, tell me how the america tells the difference between
PRC chinese and singaporeans???
Want somemore wild imagination? 
