No matter who we elect or what stance they take toward the world, it is inevitable: more terror is coming. The technology is too advanced and too accessible in a world that is already horribly broken. I have no doubts that we will live to see more apocalyptic events--not because of prophecy but arithmetic.
The unique claim of the Church, however, is that the worst thing that could ever happen has already happened: God died. We crucified the Son of love. And yet God has overcome the forces of death, with resurrection. This, and only this, is the reason we are able to live in the world without fear.
Now the worst case scenario is not something that evil men might to do us--the worst thing would be that we prove to be unfaithful to Jesus. The tragedies inflicted on us by people who have no light, no love, no gospel, and no truth pales in comparison to the tragedy of people who have the light of Christ denying the poor, the alien, the stranger, the fatherless, the widow. The pain inflicted by men full of devils is far less surprising than indifference toward suffering from the people of the cross.
No violence in the world could ever be as tragic as when the Church ceases to be the Church.