He is very optimistic that a ‘tipping point’ has been reached but believes they’ll be one big godalmighty pushback from the religious right, especially the Catholic Church, which does have clout in Oz. He reports today that the Oz equivalent of MoveOn is running a campaign, which is an enormous help with yesterday’s development.

Labor definitely lost votes on this issue to the Greens at the last election, including their first lower house seat. It almost lost three others, all ‘metropolitan’ inner city seats. Arbib’s move is partly doing the right thing – his comments related to his children, nicely positioning this as a ‘family issue’ – but are also a political calculation aimed at winning back some of those lost votes.

Gillard’s position is simply that Labor conference has to decide. At the last one marriage was narrowly lost and it seems likely that at the next one it will win. I don’t think your characterisation of it as a left-right issue in Labor is correct. The Labor opposition is largely from Catholic MPs. There are also a number of opposition (conservative) MPs in support.

Marriage is a Commonwealth responsibility according to the Australian Constitution and Commonwealth power trumps State power in its areas of constitutional competence. The States control all other aspects of family law, however. So the proposed legal strategy has all sorts of fascinating constitutional wrinkles.