Why did demobilization after world war i lead to a temporary economic downturn?

Someone told me that war was fixed because it is used to bring down the population and so the government does not have to pay the pension of the killed solders. Because why did they not killed Hitler sooner and why did they not give the solders protection on D-day. So it is all the governments fault. and what will happen after this recession.

workers of lowell mills were greatly benefited for the waltham type of work which was more a paternalist kind, trying to protect the integrity of this little girls coming from small farmers and providing an adequate place of work, this in an effort to avoid the issues of bad place conditions and immorality that the people in bigger industrialized cities of great britain were experimenting.

me with my last question i posted