No one's suggesting that.Don't believe the hype. It's weapon supply lobby groups and nationlistic politicians trying to feather their bed.
If you think an unprovoked China would attack Australia you've been sucked in and probably watch sky 'news' which is not a legitimate news source.
The most likely scenario would be one of our naval ships being struck with a Chinese missile in the South China Sea whilst conducting operations within a US Carrier group. Dead Australians. Then we would be at war with China.