It’s the demography, stupid.

There are a lot of different reasons this is turning out to be such a politically hot summer in so much of the Western world. But one way to understand this season’s acrimony — from the protests of the indignati in Spain and Greece, to the budget deadlock in Washington and even to the tragedy in Norway — is as diverse symptoms of a shared condition: The West is getting old. That demographic fact is becoming a generational war, and there is every reason to believe that in the coming decades it will get worse.