Depends on what is being defined as “cult activity”. If laws are being broken then of course the government needs to step in. If people are being hurt, weather they are apart of the cult or not, something needs to be done. BUT you cannot infringe on the rights of individuals to practice their chosen religion or lifestyle. If “cult activity” is using drugs and abusing members then it needs to be stopped, but if it’s praying to a giant invisible spaghetti monster and living together on a farm there’s not anything that could (or should) be done.