A lot of blogs picked up on this story last week (see here, here and here) but it is still worth noting for the record (more particularly, the I-told-you-so department therof).

Esteemed Harvard political scientist Robert Putnam has said what quite a few people have long suspected but not dared say in public: that high degrees of ethnic and racial diversity destroy the conditions of social solidarity in affected communities.

The Financial Times reports:

A bleak picture of the corrosive effects of ethnic diversity has been revealed in research by Harvard University’s Robert Putnam, one of the world’s most influential political scientists.

His research shows that the more diverse a community is, the less likely its inhabitants are to trust anyone – from their next-door neighbour to the mayor.

[...] When the data were adjusted for class, income and other factors, they showed that the more people of different races lived in the same community, the greater the loss of trust. “They don’t trust the local mayor, they don’t trust the local paper, they don’t trust other people and they don’t trust institutions,” said Prof Putnam. “The only thing there’s more of is protest marches and TV watching.”

The FT has a follow-up article here. It's worth noting that Putnam intentionally delayed publishing his findings before he could find a "solution" to the problems he identified. The solution, you ask?

“What we shouldn’t do is to say that they [immigrants] should be more like us. We should construct a new us.”

Thanks for the science, Bob.