My favorite line from Maus is not a line in the panel above. Although here - "You don't understand...at that time it wasn't anymore families" - is a close second. No, my favorite line from Maus is...
Well, first - sorry - a little set-up. Artie is exasperated by his survivor father's behavior. Artie loved his mother and feels he hates his father; constantly feels guilty about the brother he never met, who died in the Holocaust; feels that his father especially holds him up to the standard of what the brother might have done and been. Artie, who is now of course a visual artist - a comix guy - longs to see his mother's story of surviving Auschwitz. But now he is about to learn that his father has burned the diaries his mother kept, for which they had both been searching - and which Artie desperately needs for his book project, to "bring balance" to it. Currently it has no balance because it's wholly the story of the manipulative father.
Vladek, the father, pretends to have had a heart attack - in order to be sure Artie responds to his latest phone call. Drop everything, he says to Artie on vacation in Vermont, and drive down to my summer bungalow - right now. So Artie and his partner Francoise begin the drive. Art sighs:
"I mean, I can't even make any sense out of my relationship with my father... How am I supposed to make sense out of Auschwitz? ...of the Holocaust?"
The key phrase is "make sense...of." He wants to understand the huge historical forces, continent-wide life in extremis, that shaped his way of understanding his family, which is to say shaped his most basic means of understanding what people do for and to each other. He cannot make sense of B (the larger force which created the smaller force) if he cannot (first?) make sense of A (the smaller force created by the larger). B made A but A must be made sense of if B is to make sense.
Another reading has it that Artie is wrong: one does not need to deal with one's Freudian family romance (love mom, hate dad, envy sibling who had mom's special love, call dad murderer for destroying mom's narrative) - to deal with one's personal neuroses - in order to be able to tell the story of the Holocaust. Personal psychic health should not be a pre-requisite for knowing how the European genocide happened, and why - and to know how to try to prevent another. If so, lots of folks would have an excuse not to learn about the Holocaust. Or, in short: Artie's idea of subjectivity is itself selfish and perhaps (in a world that understands the Holocaust too little) dangerous.
I don't agree about the danger imagined just above. Maus is a representation of the Holocaust that is constantly showing its awareness of itself as a representation - that it is opaque; that it is the survivor narrative filtered through layers: (1) anger and damaged memory; (2) loss of crucial perspective; (3) a neurotic teller of the tale. We need to know that in order to know how hard it is to "make sense of" something that would seem to be objectively knowable as a story but is utterly dependent on a knowledge of the subjectivity that nearly prevents it every time.