I have thought about this matter long enough.
In my time on earth I have realized that people can do wrong.
So why would God as sovereign as he is put rulers in charge over people.
If you research the origin of kings then you will see that it was people who wanted one,not God establishing one.
God let it be.
Please read this:
1 Samuel 8:5-7
And said to him, Behold, you are old, and your sons walk not in your ways: now make us a king to judge us like all the nations.
But the thing displeased Samuel, when they said, Give us a king to judge us. And Samuel prayed to the LORD.
And the LORD said to Samuel, Listen to the voice of the people in all that they say to you: for they have not rejected you, but they have rejected me, that I should not reign over them.
As you can see,God never initiated a earthly king over people.He allowed it.
God is the true King of all the earth:
For God is the King of all the earth: sing ye praises with understanding.