If you want peace, work for justice.
Peace is not merely the absence of war. Nor can it be reduced solely to the maintenance of a balance of power between enemies. Nor is it brought about by dictatorship. Instead, it is rightly and appropriately called "an enterprise of justice" (Is. 32:7). Peace results from that order structured into human society by its divine founder, and actualized by men as they thirst after ever greater justice.
Excessive economic, social and cultural inequalities among peoples arouse tensions and conflicts, and are a danger to peace.
To wage war on misery and to struggle against injustice is to promote, along with improved conditions, the human and spiritual progress of all men, and therefore the common good of humanity. Peace cannot be limited to a mere absence of war, the result of an ever precarious balance of forces. No, peace is something that is built up day after day, in the pursuit of an order intended by God, which implies a more perfect form of justice among men.