Of course the increase in the number of democracies is the sole cause of the decline in the number of wars. Other factors, not least the ending of Cold War ideological conflicts, have also played a role. And in some cases peace may have made democratisation possible, rather than the other way round. But a number of studies do show that democracies have very low levels of internal violence compared with non-democracies. When you think about it, that is what you would expect.
Democracy is, in essence, a form of non-violent conflict management.
But a note of caution is in order. At such times different groups can become more conscious of their unequal status, and nervous about each other's power. Too often, they resort to pre-emptive violence. But that should not discourage us from urging the right sort of democratisation, as part of our development policies. Good governance, of course, means much more than democratisation in a formal political sense.