A California-based CEO learned a lesson that one would assume would be obvious in 2016: You don’t threaten to kill people on social media. You don’t even joke about it. And you especially don’t threaten to assassinate government officials; most notably a newly elected U.S. president.

But that’s exactly what Matt Harrigan, CEO of the IT security company PacketSled, did on a Trump supporter sub-Reddit over the weekend.

Mr. Harrigan clearly writes, “I am going to kill the president. Elect.” Then goes on to say, “Bring it secret service.” And most shockingly goes into details with “Nope, getting a sniper rifle and perching myself where it counts. Find a bedroom in the whitehouse that suits you mother******. I’ll find you.”

Sunday afternoon after his comments started making the expected rounds, Harrigan took to Twitter to apologize and pass the entire thing off as a joke of poor taste and regretted his “lack of judgement and offensive commentary.”

After reading as much of the conversation as possible, I’m going to do something the left would never do for someone on the right and give him the benefit of the doubt on this one. If read in a certain generous tone and taking him at his word that it was all a joke, one could see how he might have been joking. A very unfunny joke that undoubtedly will have the Secret Service bringing it to his doorstep.

In the age of social media, death threats are all too commonplace, despite platform administrators doing their best to address and sanction anyone who makes them. But, long before social media, we all knew that threatening to assassinate a president was a social taboo we all agreed on, no matter what side of the political spectrum we fell on.

It would seem that Mr. Harrigan has learned his lesson, albeit a bit late. Let’s hope that others will learn from his example of what not to do. Ever.