I agree that it is a silly analogy. Because as soon as someone points out the impossibility to keep your children from hurting one another; then the analogy no longer counts, because God is more powerful. Calling the police does not stop someone from hurting another person. The police can't do anything unless a crime has been committed (though a threat is also a crime; there might not be a threat given first). So calling the police does not do it. Is there anything else that anyone can think of?
In what way do you think God can stop all the evil that is in this world? Without policing people's every move, or smiting everyone who would harm others? Because one careless, thoughtlessly cruel word or act can start a cycle of hurt, anger, and even violence/fueds. People have to change what is within them in order for the world to change.
So perhaps everyone who might make that change is being given opportunity TO make that change.
And again, as I said earlier... there are many who belong to Christ and God who are asking that the entire place be spared for the sake of just the few 'righteous'. Or innocent. Like Abraham did concerning Sodom and Gomorrah. Who ask for mercy for all; who ask for time and forgiveness for all.
Peace,
tammy