This question has puzzled and troubled thinkers throughout human history. Based on humanity's historical experience, it would appear that a "strong tie" CANNOT be developed between law and morality on the one hand, and the present world on the other. "Realism" requires that we accept that a weak tie is all that we can actually achieve. Why? There is no consensus on the appropriate content of either law or morality! Utopian scenarios consistently eliminate politics from their societies, on the premise that a general agreement on the content of law and morality, is possible. But there is no evidence that such a state of affairs could ever really be achieved!
As I suggested in my answer to another ResearchGate question, humanity has no prospect of establishing a "good" government. What we can only aim for is "the least worst government" that we can establish and maintain in the real world. Perfectionism is NOT an appropriate aspiration for this world. Excesses of government have usually followed precisely those attempts to implement perfectionism! The perspective that is needed is Pragmatism rather than Perfectionism.
But your view that "humanity has no prospect of establishing a "good" government."
Not acceptable at all. Sorry to say, But I have to say every act of human being directly or indirectly for and only for humanity. When you are mentioning government as good government in that case we can't imagine any situation without fixing norms for humanity.