There's a lot of noise by professional and hobby firebrands who want to prop up mainland China as the new evil empire or something, but the ADIZ (air defence identification zone) story is rather not newsworthy. I can tell it's rather not newsworthy because the Japanese did the same a few years ago and few news organizations did deem it newsworthy.
Here's a map; now figure out yourself whether this ADIZ makes mainland China look more aggressive than Japan:
|(c) Maximilian Dörrbecker, from de.wikipedia.org|
To get agitated about East Asian disputes easily is an early (and stupid) step towards getting involved in needless (stupid) hot conflicts in distant East Asia.
The usual suspects cry foul about this new ADIZ.
The usual suspects are stupid and dangerous.
Don't believe them. Think for yourself.