Richard Tsukamasa Green rightly notes that Thomas Kuhn would not be surprised by the fact that the Great Recession has barely changed anyone's minds about anything. Instead, as Scott Sumner (at the end) and Paul Krugman both in different ways imply if the intellectual climate changes for the better it will be because it changes what subjects and methods young people think are interesting.
"Truth never triumphs—its opponents just die out," said Max Planck, "science advances one funeral at a time."
That's one of those quotes where I'm not sure the famous guy to whom it's attributed ever actually said it. But it correctly captures the contours of change. Ideas that are at the margins in one cohort may become mainstream in the next because they seem more appealing or fruitful or relevant. But already established figures very rarely change their views about anything that's important to them. Instead they apply their intelligence to rationalizing their own desire to not switch views. And since we're normally not interested in the opinions of stupid people, we find that smart people are very good at applying reason to the task of rationalization.