杏吧原创

Since 1945, the world has been 鈥� comparatively 鈥� peaceful, with only relatively localised wars. Some believe that this 鈥渓ong peace鈥� is the beginning of a new, conflict-free era in human history. But a new analysis suggests it could just be a blip, and that another major war could be around the corner.

The long peace began after the second world war and has held for over 70 years. In his 2011 book The Better Angels of our Nature, Harvard psychologist Steven Pinker argued that if we make the right choices it could well become permanent.

To find out if the long peace really does represent a significant change, of the University of Colorado in Boulder analysed the frequency and size of conflicts between 1823 and 2003, using information from the project, which has been gathering data on wars and conflicts since 1963. Over the 181-year period, there were 95 recorded wars: one every 1.91 years on average.

Clauset measured the size of each conflict by comparing the number of soldiers killed. The second world war was the worst, killing 16.6 million. He defined a large war as one in the top quarter by military casualties: such wars claimed more than 26,625 soldiers鈥� lives.

Clauset split his study period into three. In the first period, prior to the first world war, there were 19 large wars, occurring every 6.2 years. In contrast, the long peace since the second world war only saw five large wars, one every 12.8 years.

Not so peaceful

During the middle period, the 鈥済reat violence鈥� encompassing both world wars, there were 10 large wars, or one every 2.7 years.

This might seem to support the idea that the long peace really does constitute a period of unusually low conflict. But, statistically, the great violence and long peace cancel each other out, so the rate of wars over the last 100 years 聽is roughly what it was in the 1800s. So the long peace may not be so special.

鈥淭he large number of severe wars during the great violence period effectively balances out their relative absence during the long peace period,鈥� says Clauset. The apparent long peace could simply be a 鈥渟tatistical fluke鈥�, he says.

Clauset also estimates from the data that conflicts as large as the second world war would occur on average every 205 years. That implies we need over another century of peace before we can be confident the long peace is a genuine departure.

In other words, the underlying tensions that periodically trigger huge conflicts have not necessarily been dissipated by the long peace.

The findings 鈥渆mphasise the profound importance of continued efforts to ensure the long peace endures,鈥� says Clauset. 鈥淚t may be that the mechanisms increasing the likelihood of war are simply the unravelling of these peace-promoting types of mechanisms, such as the spread of democracy, peace-time alliances, economic ties and international organisations.鈥�

However, Clauset鈥檚 study is 鈥渄efinitely not the final word鈥� because he only looked at the incidence of wars and not their underlying causes, says of the University of Oxford, UK. 鈥淧art of the argument for the long peace rests on changes in the world we鈥檝e seen in recent decades 鈥� including democratisation, trade, international organisations and cultural shifts 鈥� which make it more likely that the world is becoming more peaceful. It would be careless not to take these arguments seriously.鈥�