Though most climate scientists are confident of this theory, they have had, so far, to rely on indirect evidence for it.

ECONOMIST: Climate change: Getting real | The

Indirect evidence of unhappiness is equally hard to gather, since so many potential proxies, such as drug abuse and wife-beating, are hushed up.

ECONOMIST: The poor: The mountain man and the surgeon | The

If Washington uncovered evidence of direct or indirect Iranian terrorist activities in America, for example, even the Obama administration would have to consider direct retaliation inside Iran.

CENTERFORSECURITYPOLICY: What if Israel strikes Iran?