Last October, amid the din of the Arab uprisings, the euro-zone crisis, the lingering effects of the Japan earthquake, and the US gearing up for a election season, a quiet milestone was passed: the world population hit the seven billion mark.

This is, on one level, very good news. It means that advances in medicine, nutrition, and education over the past six decades have dramatically raised life expectancies, reduced infant mortality rates, and eradicated previously fatal diseases. Over the past 60 years, we have become healthier and wealthier than at any time in human history - and yet, still, we stand on a precipice.

Of those seven billion humans on our planet, nearly half are under the age of 24.

In many of the poorest and developing countries, those numbers are even more stark, with 60 to 70 per cent of the population falling into that age group, particularly in poor and developing countries unable to cope with the demands of young populations. For example, three out of four Nigerians are under 35. In Yemen, the numbers are even more stark. Three out of four are 25 or under. Across the Middle East and North Africa region, two out of three people are 29 or younger.

We are currently living amid the largest cohort of youth in human history. Young populations can be a demographic gift or a demographic bomb. A gift when governments effectively employ them, deriving sustainable productive value from their labour while the young people derive meaningful work experience, raise their incomes, marry, have children, invest, and continue the cycle of life.

The next decade, however, will likely see some demographic bombs blowing up across the world as youth bulges push against weak or underperforming economies and unemployment and underemployment plague societies from Nigeria to Pakistan, from Egypt to large parts of India and sub-Saharan Africa, and in many European countries.

While this environment will inflict damage on men and women alike, the effect on young men will prove to be more destabilising.

The world over the next decade will be defined by the Angry Young Man, born amid this historic baby boom, and now entering the netherworld between youth and adulthood, unable to find a job, angry at his government, hyper-aware of the inequalities around him, frustrated by corruption, and connected to the outside world through social networking sites and satellite television. From Avenue Habib Bourguiba in Tunis to Tahrir Square in Cairo, from Athens and Tehran to Delhi and Karachi, the angry young man, fist pumping the air, has become a feature of our world.

If Mohammad Bouazizi, the Tunisian vegetable vendor who lit himself on fire in protest at his unjust treatment by municipal authorities - setting off the chain of Arab uprisings - represents the hopelessness and frustration felt by many young men across the developing world, the young Egyptians who fought each other to death in a soccer stadium represent the angry young men, frustrated by a world that is seemingly passing them by, lashing out at enemies, real or imagined.

Currently, three out of every four humans on this planet lives in Asia or Africa. In some instances, such as China, economic reforms over the past three decades have lifted 300 million people out of poverty and perhaps even more importantly, given young Chinese hope in their future even if the headlines of Chinese growth often belie the reality of the difficulties. To be sure, there are still angry young men in China, but far fewer than would be were it not for its three decades of 10 per cent growth.

Jobs will be critical to tempering the mounting anger. The International Labor Organization estimates that 13 per cent of youth worldwide are unemployed. In the Middle East and North Africa, particularly in the oil-importing and populous states of North Africa and the Levant, youth unemployment is closer to 25 per cent. This lack of economic dignity coupled with a lack of political dignity stoked the fires of the Arab uprisings.

To some extent, the rise of the Angry Young Man is a manifestation of the "success" of the past six decades. Educational opportunities have grown. Technological advances connect us all. Thus, the Angry Young Man is often educated and healthy and eager to contribute to society, only to find successive doors shut, but a world of plenty on display on Facebook. The Angry Young Man is not usually poor. The reality is that most young men who join extremist groups or engage in organised militant activity tend to come from lower or middle classes, not the absolute poor, and often have a college education.

This pattern repeats itself across the developing and emerging world, and increasingly in Europe amid recession. In Spain, nearly half of young Spaniards are unemployed. In Nigeria, where 75 per cent of the population is under 35, the rise of the Angry Young Man is posing serious concerns for Africa's most populous country. Militant attacks in the north have created a warzone-like atmosphere and an attempt to end fuel subsidies spawned nationwide rioting and looting. Nigeria will never fulfill its enormous potential unless it manages to transform the angry young men into productive, employed young men.

But back to the seven billion mark. Most of those new babies entering our world will be born in Asia or Africa, and into countries that are poor or developing. According to a report by the United Nations Population Division, by the year 2030, Africa's population will be roughly equivalent to the population of North America, Europe, Latin America and the Caribbean - combined. The population of sub-Saharan Africa could double or even triple in the next 40 years.

That's a lot of new potential angry young men, striving for dignity but facing a world of hopelessness.

The writer is a senior fellow at the New America Foundation and a senior adviser at Oxford Analytica