由于海盗在公海实施犯罪，而公海不属于任何一个国家的领海，因此就产生了一种思想：他们是人类的公敌，任何国家头可以起诉他们。
Because pirates committed their crimes on the high seas, beyond the territory of any state, the idea developed that they were enemies of humanity whom any state could prosecute.