All great leaders since Moses have known that a feared enemy must be crushed completely. (Sometimes they have learned this the hard way.) If one ember is left alight, no matter how dimly it smolders, a fire will eventually break out. More is lost through stopping halfway than through total annihilation: The enemy will recover, and will seek revenge. Crush him, not only in body but in spirit.
4 Ways to Kill or be Killed
1. Do not sympathize with your enemies.
Your enemy will bide his time and strike back when you least expect.
2. When you pity or hope for reconciliation, it will make you hesitate.
They may act friendly for the time being, but they will eventually destroy you
3. An enemy that is left around is like a half-dead viper that you nurse back to health.
You only strengthen their fear and hatred of you.
4. Give your enemies nothing to negotiate, no hope, no room to maneuver.
Do not humiliate, yet nurture these resentful vipers who will one day kill you.
This is all the truer with a former friend who has become an enemy. The law governing fatal antagonisms reads: Reconciliation is out of the question. You must exterminate, crush, and deny them the chance to return to haunt you.
Such is the case of Hsiang Yu and his enemy Liu Pang. Hsiang had proven his ruthlessness on many an occasion, but with Liu Pang he acted differently. Every time he had his rival in his hands, something made him hesitate—a fatal sympathy or respect for the man who had once been a friend and comrade in arms. But the moment Hsiang made it clear that he intended to do away with Liu, yet failed to accomplish it, he sealed his own doom.
Liu would not suffer the same hesitation once the tables were turned. Now Hsiang Yu was on the run from Liu and when he came upon a small group of his own retreating soldiers, he cried out, "I hear Liu Pang has offered one thousand pieces of gold and a fief of ten thousand families for his head. Let me do you a favor." He then slits his own throat and dies.
It is not, of course, a question of murder, it is a question of banishment. Sufficiently weakened and then exiled from your world, your enemies are rendered harmless.
They have no hope of recovering, insinuating themselves and hurting you. And if they cannot be banished, at least understand that they are plotting against you, and pay no heed to whatever friendliness they feign.
Sometimes It Is Better To Let Your Enemies Destroy Themselves
Leave your enemy an escape route. A retreat is the ultimate demoralizing defeat.Let them be the agents of their own destruction. The result will be the same.
The risk of crushing an enemy is you embitter them so much so that they spend years and years plotting revenge. Do not let your guard down, but simply crush them again.