This idea that God is ruling only in Heaven and not entirely on Earth, because corruption and evil is present, does not agree with the Bible. Imperfect state of things on Earth does not diminish God's kingship on Earth:
Job 34:12-13 Yea, surely God will not do wickedly, neither will the Almighty pervert judgment. Who hath given him a charge over the EARTH? or who hath disposed THE WHOLE WORLD?
Further in the same passage:
Job 34:18-20 Is it fit to say to a king, Thou art wicked? and to princes, Ye are ungodly? How much less to him that accepteth not the persons of princes, nor regardeth the rich more than the poor? for they all are the work of his hands. For his eyes are upon the ways of man, and he seeth all his goings.
(Some translations render Job 34:18 as "he says to kings 'you are wicked!' and calls princes 'worthless man!'". But no matter how translated, God is above kings and princes of the Earth. King of kings.)