An admittedly foolhardy (but no more than the rest) attempt to assess the legacy of Barack Obama.
From Beijing to Brighton, billions of people now can't imagine life without supermarkets. But what forces push us, as we push our carts?
The world has virtually wiped out polio, eradicated smallpox, and slowed the spread of HIV/AIDS. But when it comes to the deadly influenza virus, all governments seem to do is panic.