I am the Lord - I am Yahweh - proved to be such, as the connection demands that we should interpret this, by sending to Babylon and bringing down your oppressors. This interposition in destroying Babylon would be a demonstration that he was Yahweh, the only true God, and their God.
The Creator of Israel - (See the note at Isaiah 43:1).
Your King - Ruling over you, and showing the right to do it by delivering you from your foes.