In 2 Kings 14:23-27 there is a perfect illustration of Proverbs 21:1 ("The king's heart is like channels of water in the hands of the Lord, He turns it wherever He wishes"). In verse 24 it says Jeroboam II, "did evil in the sight of the Lord, he did not depart from the sins of Jeroboam." Not departing from the sins of Jeroboam was a serious offense because we find out later in 17:21-23 that sinning like Jeroboam was the reason Israel was cast into exile. So, that being said we should be shocked to find that verse 27 says "[God] saved them by the hand of Jeroboam (II) the son of Joash." Though Jeroboam was an evil King the Lord used Him to restore the border of Israel (14:25) in response to the affliction of Israel (14:26). Of course Jeroboam II had no clue he was being used by God to respond to this affliction.
So, God is in control of even the most evil world leaders accomplishing His good purposes (Rom. 8:28). Also, God many times sees fit to answer prayer through those who rebel against Him.
I guess this post doesn't really call for much interaction. I just came across this passage this morning and wanted to jot down some thoughts.