KEY POINTS:
My children's old primary school used to hold an ethnic food festival every year. One year I'd make chop-suey for the Samoan stall and the next it was kebabs for the Tongan barbecue. Don't ask me what's Tongan about kebabs but they always sold out.
Of course, it takes more than one Friday night a year to knit together a diverse school community but even if there wasn't cross-cultural bonding taking place over the samosas and sausages, we were at least reminded of the one thing we shared as we picnicked with our kids. We were all families who cared enough about our children to make the effort to be there.
Robert Putnam, the Harvard public policy professor who popularised the concept of "social capital", would have approved. We were building social capital. We were connecting with others. We were building trust.
Which, according to a study of American communities led by Professor Putnam, is not what happens in most ethnically diverse communities. The more diverse the community, says his research, the less trusting it is. And lack of trust results in less social capital and social solidarity.
Putnam defines social capital as social networks and the "associated norms of reciprocity and trustworthiness".
Social networks determine our level of income and powerfully affect our ability to get things done, which is why fundraising efforts in most parts of south Auckland are seldom as successful as those in Devonport.
Putnam argues that social and civic connections make individuals and communities stronger in tangible ways, producing better government and lowering crime. They even make us happier.
As Putnam writes: "Much evidence suggests that where levels of social capital are higher, children grow up healthier, safer and better educated, people live longer, happier lives, and democracy and the economy work better."
In his best-selling 2000 book, Bowling Alone: The Collapse and Revival of American Community, Putnam showed how plummeting social capital was impoverishing Americans and their communities. Increasingly disconnected Americans signed fewer petitions, belonged to fewer organisations, knew their neighbours less, met friends less frequently, socialised less with their families and were even bowling alone.
It was with the aim of rebuilding community bonds that Putnam and his team began the largest study of social capital ever conducted, surveying levels of civic engagement among 30,000 Americans in 41 areas over five years.
What the professor didn't expect, or particularly want to find, were the negative effects of immigration and diversity on social cohesion.
Far from there being unity in diversity, the study found that in the face of increasing diversity, people of all ethnicities tended to "hunker down" into their shells like turtles. It wasn't, as Putnam wrote in the June 2007 issue of Scandinavian Political Studies, that diversity produced "bad race relations or ethnically-defined group hostility".
"Rather, inhabitants of diverse communities tend to withdraw from collective life, to distrust their neighbours, regardless of the colour of their skin, to withdraw even from close friends, to expect the worst from their community and its leaders, to volunteer less, give less to charity and work on community projects less often, to register to vote less, to agitate for social reform more, but have less faith that they can actually make a difference, and to huddle unhappily in front of the television."
None of which is particularly helpful to those of us who've often preached the virtues of multiculturalism. Were we deluded all along? Is a multicultural utopia really the stuff of PC dreams? Those who've always opposed immigration would answer resoundingly in the affirmative.
And, indeed, Putnam says we have to face up to the fact that living with diversity isn't easy. Interracial interaction can be "cognitively demanding", as researchers at Dartmouth College in the United States found when they used brain imaging to monitor the effects on white people of being around black people. They found that the act of suppressing racial bias around black people is mentally exhausting.
Not that Putnam is recommending a halt to immigration, as happened in the US between 1924 and 1964. He's at pains to point out that immigration and diversity are increasing and inevitable facts of life for most modern societies, including ours here in New Zealand, and should be seen as a challenge rather than an insuperable difficulty.
In the long run, there's a cultural and economic upside to immigration, says Putnam, but public policy needs to speed things up by reinforcing community integration and creating a shared sense of citizenship. He's encouraged by the way immigrants were brought into the fold in the US in the 1930s and 1940s through "civic nationalism", which celebrated American ideals through civic practices like the Pledge of Allegiance, that "made you a perfectly good American, even if you weren't a WASP".
He cites the examples of the now colour-blind US Army, and the Christian evangelical megachurches - "the largest thoroughly integrated gatherings [he and his research colleagues] had ever witnessed" - as reasons for optimism.
There's nothing to stop societies like ours redrawing more inclusive lines of identity. We just need to stop complaining about how new migrants keep to themselves and refuse to integrate and become more like "us", and start expanding our sense of who "we" are.
