Australia Day is perhaps unique. There are few countries in the world that conduct such extensive self-examination on their national day.
Today, within these pages, on the airwaves and on our television screens, there will likely be the usual exchanges between cultural warriors. The complaints will by now be familiar.
There are those who will say that to celebrate the national day is to celebrate a day of invasion, and that any patriotism is just disguised racism. As for others, they will denounce any pause for reflection as collective self-loathing or political correctness run riot, and declare anyone not aware of the perfection of the Australian achievement might as well renounce their citizenship.
Such divisions are unlikely to be reconciled any time soon. Yet Australians can be confident that much common ground exists.
There are few among us who don't have a genuine affection for our landscape. And we can see something of the national character and spirit in each of us: an informal friendliness and generosity, a dislike of pomposity, a belief in people's innate equality, an ability to rise to our best in times of adversity.
These are cultural bonds that we share, alongside a rich diversity. Once it could have been said that Australians all loved "football, meat pies, kangaroos and Holden cars" as the 1970s advertisement claimed. Our tastes and lifestyles are no longer so uniform or homogeneous. But at the same time, our Australianness remains distinctive.
This is one of the great enduring achievements of Australia over the past six decades. We have managed to incorporate successive waves of immigrants - from Europe, Asia, Oceania, Africa and the Americas - into a stable society and national culture. And all, for the most part, without major strife or conflict.
There have been some troubling episodes. But occasional outbursts are of a different order to the challenges faced by other countries that haven't managed immigration as well as we have. One thinks of the experience in Europe, where some minorities face permanent disadvantage and overt structural racism.
In Australia, immigrants have tended to enjoy opportunity and social mobility. The Australian experience has shown that unity and diversity - cohesion and difference - needn't be conflicting values. How have we managed to do this?
It hasn't all happened organically. Our unique policy model of multiculturalism goes a long way to explaining our success. But during the past decade or so, multiculturalism became something of a negative word. In many people's minds, it seems to privilege cultural diversity over national identity. It seems to licence separation rather than integration.
The rejection of multiculturalism by leaders such as Angela Merkel and Nicolas Sarkozy has led many Australian commentators to do the same.
Extrapolating from Europe amounts to a troubling cultural cringe. For Australian multiculturalism has always been an unambiguous nation-building exercise. Europeans have typically looked to us to learn lessons, not the other way around.
At its heart, our form of multiculturalism has been about citizenship. Any right that citizens have to express their cultural identity and heritage has been balanced by responsibilities to adhere to parliamentary democracy, the rule of law, equality of the sexes, freedom of speech and English as the national language.
In other words, we have allowed cultural diversity to flourish but within the firm limits of a national civic culture. Australian multiculturalism hasn't been a case of diversity for its own sake.
This social contract will be renewed today across the nation. More than 13,000 people will be conferred Australian citizenship.
At the many ceremonies taking place, all of them will be taking the same pledge of loyalty "to Australia and its people, whose democratic beliefs I share, whose rights and liberties I respect, and whose laws I will uphold and obey". Increasingly, these ceremonies are becoming part of a new ritual of Australia Day.
They have become occasions for Australians, new and old, to share their bond as citizens. Existing Australian citizens can take a pledge to affirm their own citizenship. What such rituals do underline, however, are the civic values that we all share as Australians - and that we all can proudly sign up to.
In parks and backyards in our suburbs and towns, there will be many Australia Day barbecues taking place. Among those revelling most enthusiastically in our national day will be some who celebrate by sharing different foods from the traditional barbecue fare. But they will be doing so as proud Australians. Their celebration of the day is a clear sign that we are flourishing as a mature and relaxed multicultural Australia.
Rauf Soulio is chairman of the Australian Multicultural Council.