the problem is you've to know the techniques. from my knowledge, they set the brush fires surrounding the brushes (of the on-fire area) so the "controlled" fire eat up the available fuel before the wild fire reaches the perimetre. it still has a lot of risks, of course (hahaha "backfire").
for racism, i haven't connect the analogy completely yet. you're suppress a certain ethnicity the other suppression will eventually die down too?
