There might be a couple of ways to approach this question.  The first line of answering would lie in the ultimate recognition of the Nazi power.  The depiction of the Nazi control in the book is one where, even though the war is in its final stages, there is more of a drive to embrace Hitler's "Final Solution."  The rise of the Allies does not automatically translate into reducing the impact of the Nazi slaughter of those deemed to be "enemies."  In this, the resistance faces little chance of overall success because the Nazis forces are too strong.  Along these lines, Wiesel is trying to make a larger statement about the condition of human beings.  The resistance works if the intended of the victims see themselves as being able to coalesce and present a cohesive front.  I think that Wiesel is suggesting that one of the real horrors of the Holocaust was how all human beings were subject to dehumanization.  The Nazis dehumanize their intended victims, who in turn, dehumanize one another.  This idea is seen throughout the work.  Moshe the Beadle, Madame Schachter, the betrayal of parents by their children, and of children by their parents, and even, Eliezer himself to his own father, represents how the resistance could not really take a hold.  The dehumanization that progresses throughout the narrative is one that precludes the full embrace of the resistance movement.  At the same time, the fear of death and its inescapable presence also precludes the resistance being able to take a full hold in the narrative.