Imagine if that instead of issuing the Emancipation Proclamation in 1863 that abolished slavery, Abraham Lincoln decided to put the question of whether slavery was a good idea to a national vote.

America was in its third year of a brutal civil war, after all, which was partly a result of the battle between abolitionists and those who supported enslaving African-Americans.

How do you think that poll would have worked out? And what if he’d decided to give the advocates of slavery the money to fund a public campaign?

And therein lies the problem with leadership on core human rights issues. There will always be those who find reasons to defend the status quo despite compelling ethical arguments and do so in the face of majority support for change.

That’s where true political leadership comes in. Change will always be resisted by some elements in society.

We don’t just elect leaders to manage our economy. We elect them to put us on the right side of history and to uphold the values of liberal democracy. Those values, however flawed, are ones that espouse equality for everyone.

When it comes to marriage equality the ethical argument is compelling. Why, in a liberal democracy that separates church and state, would we deny people who love each other the right to be married?

Religious groups will still have the right to speak freely about their views – it’s enshrined in our Constitution in Section 116 – and we don’t believe in restricting religious freedom.

That doesn’t mean that everyone has to get married in a church. But there are now plenty of churches and other places of worship that will marry same sex couples.

One of the major problems with a plebiscite is that it is highly unlikely to result in Australians getting a more complete picture about why endorsing same sex marriage is important.

We live in a world where the public sphere is increasingly dominated by a series of polemic echo chambers. This debate, particularly if it was funded by the Federal Government, would quickly devolve into a shouting match. Worse, it would result in ugly homophobic attacks on LGBTI people.

Ethics, at its heart, is about respecting and embracing difference. That’s the best of what we do in a liberal democracy.

At our worst, we devolve into manning the gates and worrying about people who are different intruding into our status quo.

So talking of what it’s like to be different, let’s conjure with this scenario. You’re a five-year old girl who just started kindergarten. Most of the other kids have a mum and a dad. But you have two mums. Or two dads.

My colleague Catharine Lumby once wrote about an episode of Playschool which inflamed conservatives. It showed a little girl called Brenna who was featured in one of the short films young children watch through the Playschool windows.

The voiceover went this way: “I’m Brenna, that’s me in the blue. My mums are taking me and my friend Merin to an amusement park.” The ABC decided to include this segment after they were contacted by a same sex couple who said their daughter felt left out when it came to the way families were represented on television.

So here’s the real ethical dilemma. Do we want to watch our political leaders play politics with human rights – such as the right for someone like Brenna to feel accepted in the playground? Or, do we want them to acknowledge that same sex marriage is a human rights issue?

In the future, to put the most pressing question clearly: Do we want real leadership or more opinion polls?