. . . to tell which way the wind blows." But a supercomputer might help:
http://www.bbc.co.uk/news/technology-14841018
"Feeding a supercomputer with news stories could help predict major world events, according to US research.
A study, based on millions of articles, charted deteriorating national sentiment ahead of the recent revolutions in Libya and Egypt.
While the analysis was carried out retrospectively, scientists say the same processes could be used to anticipate upcoming conflict."