There are those who say it's inappropriate for sporting bodies to wade into the murky waters of politics. And then there's history, which strongly indicates otherwise.
Overnight, prominent cloud-yeller Sam Newman called the AFL "obsequious, fawning, sycophantic political whores" who had "no right to get involved in political messages". This was in response to the AFL changing its logo to the word "yes" to support marriage equality.
But history shows that when sport sends a message about inclusivity and fairness, it often shifts the goalposts, if you'll excuse the pun, and changes society for the better. There are countless examples. Three which come to mind are these.
THE BLACK POWER SALUTE, MEXICO CITY, 1968
At the 1968 Mexico City Olympics, American athletes Tommie Smith and John Carlos appeared shoeless and wearing black socks at the medal ceremony, to represent black poverty. They raised their black-gloved fists in what they called a "human rights gesture".
The two sprinters were widely condemned afterwards, and were expelled from the Games. Many Americans shunned them on their return too. They made their point, though. And the world has since recognised their bravery in the midst of America's civil rights struggle.
For the record, the white athlete on the silver medal podium was the Australian Peter Norman. He knew what the men would do, and stood in solidarity with them. Carlos and Smith were pallbearers at his funeral in 2006. They said that what they saw in his eyes that day in 1968 was "love".
THE END OF APARTHEID, 1991
Sport didn't end South Africa's racial segregation and discrimination policy that ran from 1948 to 1991. But crucially, the widespread ban of South African sporting teams helped many white South Africans think more deeply about the unfairness of apartheid.
It also made countless people across the globe (who otherwise would have been unaware) both aware and angry about apartheid. And of course, it enabled this memorable and once unthinkable scene from 1995, when President Nelson Mandela handed Francois Pienaar the Rugby World Cup trophy.
Indeed it was Mandela who delivered one of the most famous speeches on the power of sport. He said:
"Sport has the power to change to change the world. It has the power to inspire, it has the power to unite people in a way that little else does. It speaks to youth in a language they understand. Sport can create hope where once there was only despair, it is more powerful than government in breaking down racial barriers."
AND SPEAKING OF RACIAL BARRIERS, WHAT ABOUT NICKY WINMAR IN 1993
If anyone really believes the AFL is misguided in weighing into the politically charged question of marriage equality, they should look no further for clarity than... the AFL.
In 1993, indigenous St Kilda player Nicky Winmar was abused by members of the Collingwood cheer squad. After the game, he lifted his shirt and defiantly pointed to his chest as though to say "I'm black and proud of it".
Today, the AFL has an indigenous round and numerous other rounds which celebrate the game's heritage and diversity. So too, does the NRL and other Australian football codes. Abuse a person racially at the game and you'll be tossed out quicker than an off pie.
Sports organisations across the world have done likewise -- with campaigns discouraging racism, violence against women, you name it. Mandela said it best. Sport really can change the world, and is much more powerful than government in doing so.
Is that really such a terrible thing?