The destruction of Old Misery's house is much more senseless than the destruction of World War II because there is no real rationale for it; this act is simply one of illegal sadistic behavior by minors emotionally influenced by the effects of war.
The destruction dealt to London in World War II was made by England's enemy, Nazi Germany during the blitzkrieg ["lightning war"--quick and severe strikes]. This bombing was intended for the purpose of ruining property and assets, weakening the country, and negating the morale. On the other hand, the destruction of Old Misery's house is but a sadistic and nihilistic prank that is completely gratuitous and with no logical rationale. In other words, there is no sensible reason to destroy Old Misery's home; the act is committed solely for the perverse pleasure that it brings to the boys.
That this act of destruction designed by T., the son of an architect, is perverse comes with a line from the story itself: "destruction after all is a form of creation." This destruction is an indication of the effects of war upon the next generation that they perform an act of the basest form of human nature. It is an act that is, indeed, disturbing, especially in the perverse pleasure derived from it by the boys and even the lorry [truck] driver, negatively affected by the cruelty and irrationality of war.