In a status quo lifetime, one loses about a handful
of good friends to death. None will get truly
desensitized.

In a war, there interval between sorrow and
survivalist-emotional-auto-pilot is minuscule.
After a short span one becomes entirely desensitized.

In the slums of America, desensitization is a slow,
excruciating process as emotions along with lives
are bled to death.