The original question had to be edited down. Paul's realization about the progression of the war is not a very hopeful one in chapter 11. He is beginning to see that the war is withering away everything for the Germans. The front is beginning to dissolve in front of the Germans' eyes. They are losing in a brutal manner and there is little that can be done to stop the attrition. The chapter begins with the bleak assessment that there is an equality of wretchedness that seems to unify the soldiers in the hopelessness of their situation: “Now we are all melted down and all bear the same stamp." The process of this "melting down" is the fact that there is little in way of reinforcements being delivered to the Germans. Additing to this is the Allied Forces being able to deliver on both new troops and munitions, realities that escape Paul's battalion and the German condition. The war has brought about a reality that death and loss become the only certainties in this war:
Shells, gas clouds, and flotillas of tanks—shattering, corroding, death. Dysentery, influenza, typhus—scalding, choking, death. Trenches, hospitals, the common grave—there are no other possibilities.
For Paul, this becomes the realization that cannot be escaped. The war's progression is one whereby German loss is inevitable. When Kat dies, it becomes a stunning reminder of how alone Paul truly is and how a war that began with the greatest of expectations and hopes is becoming a brutal reality in which suffering is the only unifying principle.