China and India will take the global leadership on climate change: they are suffering for it.

In economics, one of the most important concepts is 'opportunity cost' - the idea that once you spend your money on something, you can't spend it again on something else.

Many Liberals are rightly dismayed that on this vital issue of climate change we are not simply without a policy, without any prospect of having a credible policy but we are now without integrity. We have given our opponents the irrefutable, undeniable evidence that we cannot be trusted.

Greece is an extreme case: a country where both the level of spending and the level of taxation were unsustainable!

To the former child migrants, who came to Australia from a home far away, led to believe this land would be a new beginning, when only to find it was not a beginning, but an end, an end of innocence - we apologise and we are sorry. To the mothers who lost the maternal right to love and care for their child - we apologise, and we are sorry.

We are already experiencing the symptoms of climate change, especially with a hotter and drier climate in southern Australia - the rush to construct desalination plants is an expensive testament to that.

This is a very tough business, politics. It's easy to get resentful or full of bitterness ... (but) I think hatred hurts the hater more than the hated. So I'm looking back on my time positively.