Your knowledge of China must be very limited.  

They have had a dominant attitude since the 21st Century BC.  

They currently have the largest Army in the entire world.  2,285,000 personnel, 0.18% of the country's population.  By some measures, the 2nd largest Defense Budget in the world as well.

It's current nuclear stockpile is estimated at about 450-600  warheads.  This includes nuclear cruise missiles and nuclear-capable submarines.

As of 2011, the Chinese nuclear arsenal was estimated to contain 55–65 ICBMs.

https://en.wikipedia.org/wiki/China_and_weapons_of_mass_destruction