This is actually how God works, just read the Book of Judges, Israel lives in quiet and prosperity, they slowly fall into sin, idolatry and apostacy. God sends an enemy to overrun them, to subject them to tribute (taxes) and rule over them. Eventually it became so bad that Israel cried out to God who sent a redeemer to fight for them. The redeemer is successful, the enemy is defeated and ejected and peace and prosperity reign - until they started back to sin, idolatry and apostacy ...