In Mahabharata there are numerous didactic tales advising Kings on the rules of engagement in a political scenario. The tale of Lomasha and Palita from the Shanti Parvan (138) explains why a wise enemy is better than a foolish friend.
Deep inside a thick forest there stood a huge banyan tree. It was home to various species of wild animals and snakes. Inside a hole near the roots of this huge banyan tree lived a rat by name Palita and on one of its branches lived a cat by the name Lomasha. Lomasha subsisted entirely on the birds that would visit the tree. However, Palita always lived in fear of being killed by Lomasha and hardly ventured out his hole.