The Prime Minister's stubbornness on same-sex marriage reform might yet prevail, but it brings with it political risks - from internal divisions to something a whole lot worse. Barrie Cassidy writes.

Tony Abbott must hate the same-sex marriage issue. A Government so adept at controlling the agenda is powerless to prevent the issue periodically flaring up.

And even if the Prime Minister wins on the issue, he loses.

Abbott can encourage the parliamentary business committee of cabinet that determines legislative priorities to push the private members' bill well down the pecking order. That would have the added benefit, from his point of view, of avoiding a debate in the party room on a conscience vote.

The conservatives in the Coalition opposed to reform see that as the best short-term strategy. They are becoming increasingly nervous about where the debate is headed.

Eric Abetz, the Government leader in the Senate, for example, told AM on Thursday:

If you are on the frontbench you have a duty to support party policy, and if you can't support party policy - and I found myself in that position with the emissions trading scheme - I did the honourable thing and I resigned from the frontbench.

That surely gives a sense of how divisive the issue promises to be internally for the Coalition.

But if the issue is killed off in that way, the repercussions for Abbott and the Government could be a whole lot worse, potentially costing them government in a close election.

The public will struggle to comprehend how the Government can deny Parliament the opportunity to test the numbers on an issue that has such overwhelming community support.

Has the Prime Minister forgotten that before the election he promised that once a bill was put before the Parliament, then the party room would deal with it?

Repeated research indicates that social issues rank low in the minds of voters. But that is not to say they are unimportant.

Barack Obama beat John McCain for a range of reasons. It happens though that Obama was demonstrably to the left of McCain on issues like gay marriage and civil unions, gay adoptions, gun control and limiting the death penalty.

Abbott is otherwise politically astute. He knows that his concentration on economic management, border security and terrorism plays well.

But has he taken into account how the explosion in the social media elevates social issues way beyond levels in the past when the mass media alone controlled the agenda?

It is not just an issue for the gay community either. Far from it. The attention it gets ensures that same-sex marriage is an issue that helps define the social fabric of the nation. In turn, that means it's not an issue that will impact only in seats with a high proportion of gay voters. It can make a difference at the margins across the country. Why do you think the independent, Cathy McGowan, in the rural Victorian seat of Indi, is so anxious to be associated with the private members bill?

It helps to define the Prime Minister as well. Can he afford to be so out of step with community values?

Those opposed to reform insist there is no momentum, either here or abroad. That's denying the obvious.

The gobsmacking example of global change happened in Ireland. A conservative catholic country that two decades ago voted just 50.3 per cent at a referendum in favour of divorce, came out 62 per cent in favour of gay marriage.

In Australia, a Newspoll in 2003 put support for gay marriage at 38 per cent.

Last year, a Crosby-Textor poll put that support at 72 per cent. Just under half (48 per cent) strongly supported it.

Mark Textor said at the time:

With Australians across all key demographics supporting marriage equality in record numbers, it's fair to say the public has made up its mind, the community debate is over, and it's time for politicians to act. We will be using this landmark research to work with Government members who have yet to declare support for reform to show them they have nothing to fear.

But fearful they remain; so much so the arguments against reform are becoming increasingly illogical and inconsistent.

Eric Abetz on AM raised the question:

Are we in the Asian century or not? It's amazing how certain people try to pick and choose in relation to debates. All of a sudden the United States, which is usually condemned, is now being celebrated on the bizarre decision of a five-four majority in the Supreme Court. The Labor Party... and journalists tell us time and time again that we are living in the Asian century. Tell me how many Asian countries have redefined marriage?

Taken to its logical conclusion, Abetz was arguing that geography trumps social and cultural ties; that we should look to Asia and not the United States for guidance.

It seems to escape him that in countries like Malaysia, Singapore, Pakistan and Bangladesh homosexuality itself is illegal.

In the July issue of The Monthly, Mark McKenna wrote that Abbott "rather than using power creatively ... relies on his enemies to define his agenda".

There is no better example of that than this issue.

But his stubbornness might yet prevail. No matter the political cost, it may be that he simply cannot allow this historic reform to go through under his watch.

Barrie Cassidy is the presenter of the ABC program Insiders. He writes a weekly column for The Drum.