God angry by going against his plan hey it makes more sense to save a child who doesnt belive so you can convert them after.
Now that is why your example is stupid based on your logic you can let a child die hey if I used the example of 2 children where drowning one a beliver tho other not who will you save. Your answer would be the non beliver. Well my answer would be to try and safe both. So you see your example is not as simple as you make it out to be