The old battle between "conventional wisdom" and its debunkers isn't what it used to be. When liberal economist John Kenneth Galbraith started using the term in the 1950s, his targets were not just any widely held wrong opinions, but those that were the product of inertia and convenience. Conventional wisdom, Galbraith thought, reinforced complacency. It enabled us to "avoid awkward effort or unwelcome dislocation of life," he wrote in The Affluent Society.
Since then, of course, we've all become debunkers. (Just google the term "conventional wisdom watch" -- virtually everyone is on alert for the stuff.) But something has happened to the mainstream ideas that need to be shaken up. Today's conventional wisdom isn't complacent. Its hair is on fire. It wants us to see that climate change threatens all humanity, that the United States is in decline, that we're all going to have to work harder and longer in the future, that China is going to rule the world -- unless perhaps a nuclear-armed Iran gets there first.
The debunking impulse has also changed. Far from trying to rouse us from slumber, its role is now to offer us a cup of warm milk before bed. If you doubt this, just dip into the debate about some important element of contemporary conventional wisdom, like the idea that America's global dominance is eroding. This may seem so obvious as barely to require discussion. Yet some of our best, most independent-minded commentators on international politics, scholars and practitioners alike, are saying that your eyes deceive you: America's decline is definitely not inevitable, and might not be happening at all.