Would Australian defence of Taiwan amount to the crime of aggression?

From Pearls and Irritations- well worth subscribing to.

Mike Scrafton was a Deputy Secretary in the Victorian Department of Sustainability and Environment, senior Defence executive, CEO of a state statutory body, and chief of staff and ministerial adviser to the minister for defence.

"Arguing that Australia should go to war over any attempt by China to recover control over its own territory would be intervening in China’s internal domestic affairs, and advocating a crime against international law; the crime of aggression."