Most animals do not fight to the death, outside of predators going for prey to eat.
The only reason this is true is because every moment of combat is dangerous - which means it is far safer to chase your opponent off, whether by intimidating them or wounding them. Humans are unique in that our tool use allows us to kill our enemies with a single blow. Animals besides ants that operate in large social groups can absolutely come into conflict with other groups, and engage in what can easily be considered warfare.
If you somehow managed to hand a rabbit a pistol and teach it how to use it, I guarantee there would be dead animals near its burrow.
The only reason this is true is because every moment of combat is dangerous - which means it is far safer to chase your opponent off, whether by intimidating them or wounding them. Humans are unique in that our tool use allows us to kill our enemies with a single blow. Animals besides ants that operate in large social groups can absolutely come into conflict with other groups, and engage in what can easily be considered warfare.
If you somehow managed to hand a rabbit a pistol and teach it how to use it, I guarantee there would be dead animals near its burrow.
It also makes sense because, in a fight, you of course would use your most intimidating weapon first.