Oh, yes, if we believe He is the Messiah then HE IS KING. If we believe that he resurrected and conquered the grave HE IS THE KING of that Kingdom John the Baptizer preached about, he is the King of the kingdom he was born, died and resurrected for, he is the KING of the kingdom all the apostles preched about everywhere they went as a real conquering kingdom that would expand throughout the earth... He has been ruling on earth the moment he was put over ALL rule, power, authority, dominions ... The term Lord is a kingly title when applied to Jesus - David's kingship pass to Jesus ..."therefore let all the house of Israel know for certain that God has made him both Lord and Christ, this Jesus whom you crucified" (Acts 2).
Jesus says ALL authority has been given unto me in heaven AND ON EARTH (he did not say in heaven only) - JWs and others have come up with a "spiritual" "invisible" kingdom ... these words never appear together in the bible ..