If you haven't enabled two-factor authentication on Facebook, you should. If Facebook thinks someone has attempted to access your account, it will notify you. Now, those warnings may come if Facebook thinks the attacker is backed by a government.
In a blog post from Facebook's Chief Security Officer, the company has said that it's expanding its monitoring of suspicious login requests to include possible government attacks. While it's (hopefully) not very likely that most individuals will be targeted by a nation state, getting the specialised notifications would help curtail any damage.
Facebook hasn't clarified which governments it's watching out for, or if that includes Australia. Facebook (like many tech companies) has repeatedly expressed frustration with domestic surveillance programs. However, it's unclear if these warnings would include attacks from home, or if Facebook is just watching for foreign attacks.
Regardless, as evidenced by a sample of the notifications one might receive, the solution is still the same: turn on two-factor authentication. If a government (domestic or otherwise) tries to log in to your account, having two factor enabled will be a helpful barrier to have.