What humor is appropriate?

Why do we laugh at such terrible things? Because comedy is often the sarcastic realization of inescapable tragedy. Bryant H. McGill

 

The above cartoon is making the rounds - one of the more "sarcastic" responses to the proposition that armed teachers would make for safer schools in the wake of the Florida shooting last Valentines Day.

I am embarrassed to say it, but I found it very funny. I am embarrassed because I am well aware of the grief and terror mass shootings have caused in this country and that the parent of a child murdered in them would find nothing amusing in the chart above.

Most if not all humor has an element of pain or discomfort at its heart. From a person slipping on a banana peel to the ribaldry of Lysistrata to latest grotesque of Trump in today's editorial cartoon, harm or embarrassment or discomfort are essential components to finding something funny.

The question for me is where do we draw the line? I do not believe we should encourage or create or distribute humor that is racist or homophobic. But how about jokes that emphasize the difference between men and women (75% of all humor?) Can this be labeled sexist? Are we denigrating religion if Jesus or Mohammed or Buddha is in a comedic sketch? Can I poke fun of my own Scandinavian heritage by telling an Ole and Lena joke?

I am not trying to make any point here except to say that knowing what is appropriately funny seems to be getting more difficult each day. That I suspect there is no comedic effort that does not offend someone, somewhere. 

What yardstick do you, dear readers, use when determining whether to share a joke, a story, a cartoon? Or is humor simply something too risky anymore?