One can understand why a loving but righteous God could destroy a Sodom and Gomorrah. Modern day example.
Exactly.
If these people do not repent, they will face an extremely angry Christ Who will cast them into eternal darkness.
Sin angers Him on general principle, but the sin of corrupting children is one He especially hates and is expressly singled out for an exceptionally severe judgment.
Read Matt. 18:6 and Luke 17:2.