Problems cant be solved with the feeling of revenge:
- Germany formed an alliance with Italy and Austria-Hungary. As a counter attack France also formed another group with Russia and Britain. The formation of secret alliances is considered as the first cause of the world war I.
- Black hand society murdered the prince and princess of Austria-Hungary. Austria Hungary attacked Serbia to take revenge. The first world war started because of the same incident.
- Versailles treaty was signed along with the end of world war I. Germany was humiliated much in this treaty. The treaty compelled Germany to take the sole responsibility of the war and pay the compensation. Since Germany was insulted a lot through the treaty of Versailles, Hitler started second world war after twenty years to take revenge of it by violating the treaty.
- Rise of a person like Hitler, Groupism among the countries, failure of league of nations resulting in the out break of world war II was all because of feeling or revenge.
Therefore no problem can be solved with the feeling of revenge. The only alternative to this can be dialogue and consensus among all.