I don't recall which party decided to privatise airports, and it doesn't really matter because both major parties have embraced the principle of privatisation.
It seems the Liberals are just more gung-ho about it.
If airports are good money-spinners they should remain in public ownership for the financial benefit of the whole community.
And even if they are not very profitable they should remain in public ownership because they are an essential part of the community's infrastructure.
Public ownership is the best way to ensure that the community's needs are met.
One thing that no politician has ever explained is - how are governments generally going to balance their books when there is nothing left to flog off?
Will they finally have to resort to good economic management and live within their means?