Isaiah is a unique prophet in the way he understands and presents the events facing the people of Israel. He is not awed by the Assyrians nor does he cower in fear.
But how can he maintain this attitude in the face of certain defeat and annihilation of the people around him? Perhaps it is because he has seen the Lord in his glory and it changed his perspective. Listen to Mark Lanier explain Isaiah's perspective and may you understand that God is GOD and any trials or tests you face are simply a tool in God's tollbox for His use as needed.