Russia obviously has a significant problem with terrorism, I think everyone has heard of the attacks in Moscow including the major hostage situations that occurred there.
The Moscow attacks are synonymous with the multiple attacks in Mumbai, and the multiple IM attacks in New Delhi.
Do you ever see such massive attacks taking place in Shanghai or Beijing or Hong Kong? Not multiple, not even single. There are no terrorism-related "travel warnings" for any of these cities, unlike Mumbai and New Delhi.