When the current upheaval hit the Arab world it quickly emerged that one driving force was youth underemployment. These countries had opened colleges and universities that churned out grads for whom there weren't nearly enough jobs to go around. The kids weren't alright and eventually they took to the streets.
This underemployment phenomenon isn't limited to the Arab world. It is also setting in with the emerging economic superpowers, China and India. They too have been churning out grads faster than their economies have been able to absorb them. That's one of the main reasons the Chinese censored internet accounts coming out of Egypt.
But India and China are facing another demographic time bomb - a surplus of young men and a deficiency of young women for them to marry.
Abortion of female foetuses has led to a massive surplus of young unmarried men in India and China, raising fears of an outcast group that could threaten the social fabric.
The trend took root in the 1980s when ultrasound technologies made it easier to detect foetal sex early, according to the analysis in the Canadian Medical Association Journal.
Sons have traditionally been preferred in parts of China, India and South Korea for social, cultural and financial reasons.
The phenomenon was first spotted in South Korea in the early 1990s, when the sex ratio at birth (SRB) - typically 105 male births to every 100 female - rose to 125 in some cities.
''These men will be unable to marry, in societies where marriage is regarded as virtually universal, and where social status and acceptance depend, in large part, on being married and creating a new family,'' said the study's authors, led by Therese Hesketh, of University College London's Centre for International Health and Development.