2.Why was Japan able to avoid domination by imperial powers successfully when many other East Asian nations?

Answer 1

It is real significance of Japanese culture and Japanese nationality.
Have you ever hard "A tall tree catches much wind."?
Japanese do not like person who has too much power.

Answer 2

Er... Matthew Calbraith Perry, Opening of Japan, Meiji Restoration, etc... Ring any bell?

Answer 3

It became a colonial power itself.