You do not win that kind of war by matching the enemy resource for resource. Look at the example of early Christianity. Rome had the money, the armies, the law, the prisons, and the power to kill. The Christians had truth, discipline, community, sacrifice, and refusal to become what they opposed.
So the answer is: endure, tell the truth, do not return evil for evil, build something stronger underneath the empire, and make the enemy defeat itself morally.
You win by being harder to corrupt than you are to crush.
