Did not understand what you mean here. If you think that one day those asians can block the internet to the whole world then you are crazy (and i'm curious about the details).
If you mean that they can centralize bitcoin then such threat do not exist atm. To make it more realistic China still have to do huge investments (the more  money invested by non-Chinease miners the more China should invest). If they will loose the internet access before getting majority imho we will only benefit from making bitcoin more decentralized.