Choose your own priorities on our interactive table

Issues: conflict l global warming l disease l hunger l terrorism

The Challenge

The food crisis is increasing global political instability at a time when the risk of new civil wars is already rising. Many recently-negotiated peace settlements have left nations fragile, while the commodity boom and discovery of mineral resources in countries with weak governments have sown seeds for discord.

An introduction to the Copenhagen Consensus

Economists battle it out to rank possible solutions for the great challenges in global stability and security

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BACKGROUND

• Copenhagen Consensus: conflict

• Copenhagen Consensus: disease

• Copenhagen Consensus: global warming

• Copenhagen Consensus: hunger

• Copenhagen Consensus: terrorism

Since the Iraq war, the developed world has lost faith in using military force to reduce conflict. However, Iraq may be a misleading guide to the effectiveness of intervention.

Unlike the vast majority of conflicts, its civil war was sparked by an international war. The far more typical scenario is a relapse of political violence within a small, low-income, low-growth nation already troubled by fighting. This is the real security challenge that developed nations must deal with this decade.

Option One: Aid

Post-conflict aid designed to stop violence recurring is much more politically acceptable than the use of force. If it proves just as cost-effective - or more so - than military intervention, then it would clearly be a more attractive option.

The numbers

In a nation recovering from violence, each additional percentage point of national growth lowers the risk of conflict re-emerging by around 1.5 percentage points. This typically requires annual aid of $400m: it is very expensive.

This investment does not just reduce the risk of civil war, but also boosts growth. The overall benefits are worth nearly three times more than the costs.

Post-conflict aid therefore looks to be a good use for aid money, but not so spectacular that it would trump most other calls on scarce international public resources.

Option Two: Military intervention

Four new civil wars are expected to break out in the next decade in low-income nations.

The real problem with most peacekeeping interventions is that they are too short — the risk of renewed civil war in post-conflict situations declines slowly with time. The degree of risk reduction depends on the scale of deployment.

The numbers

Spending $850m on a peacekeeping initiative reduces the ten-year risk of conflict re-emerging from around 38 per cent to 7 per cent. A smaller military intervention would reduce the risk by a smaller amount.

Because of war’s horrendous and lasting costs, each percentage point of risk reduction is worth around $2.5bn to the world.

The economic benefits to the world from spending $1bn each year to reduce the risk of conflict add up to $12.6bn: each dollar achieves $12.60 of good.

Other Options

Conditional Aid: Linking aid to limits on military spending, to improve its cost-benefit ratio

Over-the-Horizon Guarantees: Providing (and delivering if necessary) a promise to intervene when a democratically-elected government is threatened by violence

Combined Peacekeeping and Over-the-Horizon Guarantees: Five-year peacekeeping operations, followed by over-the-horizon guarantees

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