Doug Dotson wrote:

It never fails in a thread that lasts this long that the personal insults
start appearing.

That's called "Godwins Law". From
http://www.jargon.net/jargonfile/g/GodwinsLaw.html

Godwin's Law /prov./ [Usenet] "As a Usenet discussion grows longer, the
probability of a comparison involving Nazis or Hitler approaches one."
There is a tradition in many groups that, once this occurs, that thread
is over, and whoever mentioned the Nazis has automatically lost whatever
argument was in progress. Godwin's Law thus practically guarantees the
existence of an upper bound on thread length in those groups.