Because after disasters, we tend to become more spiritual. It is sad, but at least in the thorny bush, we have roses. Similarly, in the latest event, we have war in Kosovo. And people tend to become closer together, more loving, more giving, more understanding. Also they have more of a penchant for God's knowledge, and this is a very positive side.
Christ is the only Son of God because Christ is not a person. Christ is a power that emanates from God, who creates the universe, also who can bring the creation back to Hirm. And Christ, this power, at that time has manifested fully in the person of Jesus. So we call him Jesus Christ. That means Master Jesus. Just like we call Buddha Gautama, which means Master Gautama. Buddha, Christ, are the same name for this extraordinary, only-one power which we can say is the only Son of God. So this Son of God, this only power can choose to manifest any time on this planet or any planet in order to save mankind or other beings, and bring them back to the Father when they are ready.