Ok I had a weird dream that France Attacked New Zealand and Australia retaliated and sunk French destroyers ?

I know it sounds weird but being an Aussie with plenty of Kiwi mates, after several drinks I actually drempt that we declared war on France after they fired missiles upon New Zealand, in retaliation for a Nuclear demonstration and Naval blockage. Glad I was dreaming, but how realistic would this scenario be ? Could we take France in the South Pacific if need be, ie, if they Attacked our "little brother" New Zealand ?