Labor versus Liberal, Republican against Democrat, Iran v the US, Sunni v Shiite, Catholic v Protestant, Kyle Sandilands versus everyone ... does it ever end? The conflict, the disagreements? I mean, why can't we all get along? ...
You may have witnessed a microcosm of this global friction while on your holiday break, perhaps at Christmas lunch when your creepy uncle hit his second case of Melbourne Bitter and started undressing younger relatives with his eyes. Or your auntie lectured your sister on how she should be raising her children.
Maybe granddad bemoaned the loss of Pauline Hanson to the national dialogue. A fight broke out over the music being too loud, someone stole your nan's prawns after you'd peeled them for her, your mum said you didn't phone her enough ... and then it all went downhill from there.
These are the seeds of even the most profound, international conflicts - differing points of view, attitudes, avarice, prejudices - and they can soon spiral into heated words, fisticuffs, then full-fledged warfare.
So how to nip it in the bud?
I recently heard about a new movement called "Fight Free February", designed to help people navigate difficult relationships by giving them a new way to resolve conflicts each day of the month.
I'm not sure whether the FFF organisers will endorse this suggestion, but I reckon you can defuse most strained situations by getting the antagonists on to common ground, namely a subject everybloodyone can agree on.
And because I love a list, I thought I'd create a collection of conversation subjects all Australians - even creepy drunken uncles - can agree upon.
So, whenever you feel tension mounting in your peer group over politics, religion or child-rearing practices, bust out one of these topics and ... come together!
Chucking sickies: Just a wonderful, wonderful Aussie institution that really only bothers politicians, employers and the Business Council of Australia.
Ask people for their favourite excuse for calling in ill and cheer particularly egregious or creative abuses of sick leave.
Sunshine: Unless you're a vampire, albino, Goth or farmer suffering through a drought, I reckon pretty much every Aussie enjoys a bit of warmth and light.
There are so many ways you can go with this. Where would Ray Ban sunglasses, Kresta blinds, Banana Boat and the paintings of Claude Monet be without sunlight?
Food: How good is it? Everyone loves the stuff.
Thongs: Ever heard anybody complain about thongs? They're simple, utilitarian, pretty much perfect. As a nation, I also reckon we can agree they're far more practical shoved on your feet than up your bum.
However, even the underpants version of the thong has its supporters among women and perves, and I think we can also concur that blokes who wear such garments are thoroughly deserving of mockery.
You can't lose with this subject.
Public holidays: They rule. Nominate your favourite.
If you can't agree on the beauty of these Aussie rod gods, I suggest you put your hands in the air and move away from the latte glass.
The Ode of Remembrance: Said at 6pm, every day, in every RSL in the country. A haunting, poignant, authentic, refreshing ritual that does honour to those who've died to protect this country, as well as all those who submit to repeating the words.
Drinking: While not all of us enjoy a refreshing alcoholic beverage, I think those who do can agree it's always a little more fun if you imbibe overlooking water - a beach, river, harbour, creek, dam, lake - even the backyard pool if need be.
It also gives you somewhere to pee.
Cold Chisel: This might be contentious in some inner-city, poetry-quoting, intellectual families, but the rest of us agree Cold Chisel is the greatest Australian band ever - sorry AC/DC - and if you do want poetry, Chisel's lyricist Don Walker has done it like nobody else in this country's history.
Turn it up, nanna.
What do you think all Australians can agree upon?