I don't see President Bush being polite and respectful to Saddam Hussein. So there are exceptions to when that is called for.
The question is how you define
"polite and respectful" and where you draw the line as to where it is due.

I think it is polite and respectful to posts
useful, informative responses that are free of personal threats. Others seem to think it is
polite and respectful to post specious arguments
and vacuous chatter with a mild tone.

If mildness is mostly what you bring to the list,
that does not make you an expert on what is "polite and respectful."

There are two distinct conversation styles we might pose as a model.
One is sincere, signed by
a real person with their name, and attempts to deal with the question at hand. It may be somewhat charged at times. This is well within the level of decorum in sporting events and political debates. Rules are followed and respected, though there's a little rough and tumble at times.
The other is anonymous and mild-mannered, but with cold intent to employ innuendo and prissy
complaints rather than well-conceived arguments.

Nobody is either One or the other. But there's a continuum along which we can be found performing at a given time.