How Network Theory Can Explain the Outbreak of War
Similar to our studies of stable and unstable networks in classes, Matthew Jackson and Stephen Nei of Stanford University have used a combination of network theory and game theory to study the stability of different types of global networks. Specifically, they study networks of trade agreements and military alliances and how they relate to the outbreak of war. The networks they study are comprised of a varying number of countries, each which can form a military coalition of a certain strength with another. Any given country is considered vulnerable to an attack if its own coalition is weaker than that of its opponents and if the cost of war is less than the benefit. This is similar to the ideas we have been exploring in class in game theory, that people will behave in ways to maximize their gains.
An interesting question to ask given this study of global networks is if any such network can ever be completely stable against war. That is, if in the network no country is vulnerable to an attack. Unfortunately, the only such network that is completely stable is the trivial one that is empty and has no links. Another somewhat paradoxical idea their study has shown is that global stability has actually increased with the advent of nuclear weapons. This is because it has reduced incentive to attack by increasing likely damage incurred in retaliation. Overall, it is an interesting study that uses the ideas of network stability and decision theory we have seen in class to explain historical global stability.
Source: http://www.technologyreview.com/view/531736/network-theory-reveals-the-hidden-link-between-trade-and-military-alliances-that-leads/