China is less interested in international security because it feels far less insecure than other countries. It is too big to really suffer from a single nuclear strike coming from a small rogue state; it can bear terrorist actions without a public opinion uproar against the government.
At the same time, a certain level of world insecurity serves to weaken what is perceived as U.S. hegemony. One should never forget that in the long run the U.S.-China rivalry will overshadow present international terrorism, as well as the threat of nuclear proliferation -- and the Chinese are more comfortable with their long term prospects than the Americans are.
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