There's a story from the Eastern Roman Empire of a Christian monk who was horrified by the wickedness of the emperor. He prayed to God and asked, "Why did You allow that evil man to become emperor?" God replied, "Because I couldn't find anyone worse!"
Daniel saw wicked kings reign over God's people in Babylon. It must have been extremely frustrating. In time, the Lord dethroned each proud king, but He replaced them with others just as evil.
King Nebuchadnezzar, for example, exalted himself until God caused him to live like an animal for 7 years. When he regained his mind, he praised God as the one true Ruler (Dan. 4:28-37). But the cycle of evil monarchs continued. Belshazzar, Nebuchadnezzar's descendant, mocked God and used the sacred goblets from the temple in Jerusalem during a drunken orgy (5:2-4).
We must remember that history is God's story. He reigns when the politicians we vote for get into office, and He reigns when those we oppose get elected. God is sovereign over the rulers of this world (Dan. 4:17). We can trust Him to do what is right because His "works are truth, and His ways justice" (v.37). — Haddon W. Robinson
The Most High still rules over kingdoms of men,
He gives the control to whomever He will;
All people must bow to His sovereign plan,
And know that His purposes He will fulfill. --Hess
The king's heart is in the hand of the Lord. --Proverbs 21:1