In the former Soviet Union and other formerly existing socialist countries, many of the people who made that leap from a fact -- e.g., dangers of plots supported by foreign powers exist -- to total suspension of skepticism and the conclusion that all accusations of heinous crimes, however lacking in evidence, must be believed were of peasant backgrounds.
In the United States today, many of those who make such a paranoid leap from a fact -- e.g., terrorist attacks can happen, children can be raped -- to total suspension of skepticism and the conclusion that all accusations of heinous crimes, however lacking in evidence, must be believed are quite well educated, very often in possession of advanced degrees. The paranoia about terrorist attacks mainly exists on the Right; the paranoia about child sexual abuse exists across the political spectrum, and on the Left it is motivated by noble sentiments about the importance of recognizing relations of power* -- adults and minors, parents and children, men and women, etc. -- and sentiments of automatic sympathy toward those who are structurally put in a position of less social power at least in one power relation (though A who has less social power in one relation than B may have more power than B in another relation -- e.g., Bettina is a woman, Herbert is a man, so Bettina has less power than Herbert, but Bettina is alive, and Herbert is dead, and the living have more power than the dead).
It's always easy to see other people's paranoia, but seldom do people recognize their own.
Moreover, even some who see the problem of lack of evidence may think, what if evidence, which doesn't exist yet, later surfaces? Let's err on the side of zealous prosecution in case it will.
Paranoid styles are difficult to combat.
* The same noble sentiments motivate the tendency to believe all accusations against governments even without corroborating evidence that exists among both conspiracy theorists and those who are concerned about human rights, though conspiracy theorists tend to focus on their own government and human rights activists tend to focus on foreign governments. The government has more power than individuals (besides it is always in the wrong in the eye of instinctive anti-statists, which almost all Americans are), so all charges made by individuals against the government must be always right, or at least "there may be something to it"! -- Yoshie <http://montages.blogspot.com/> <http://mrzine.org> <http://monthlyreview.org/>