Why were serial killers so active in America during the 2nd half of the 20th century?

Question

Edmund Kemper, Jeffrey Dahmer, John Wayne Gacy, David Berkowitz, Herbert Mullin are some examples.

In: 3

Answer 1

It was a period of time when it was easy to get around and operate in different areas without people getting suspicious. And you had just enough databases and police cooperation to tie the crimes to each other but not enough to investigate properly. Without the ability to analyze the evidence and look up things in huge country wide databases like we do today the police often just had to wait for the serial killer to get caught in the act.