The weapon of suicide bombing is so desperate that you aren't even left with the possibility of taking revenge or punishing anyone; the terrorist is killed along with his victims, his blood mixing with theirs.
So with truth - there is a certain moment when one can say, this is the truth and here I put a dot, a stop, and I go to another thing. A judge has to put an end to a deliberation. But for a historian, there's never an end to the past. It can go on and on and on.
The question of boundaries is a major question of the Jewish people because the Jews are the great experts of crossing boundaries. They have a sense of identity inside themselves that doesn't permit them to cross boundaries with other people.