Why is it illegal to threaten someones life online, but not illegal to show up to their home armed?

I read this article about a bunch of sore losers who showed up to the Michigan Secretary of State armed. She was home with her 4-year-old. They claim they only showed up to air their grievances. So let’s pretend that is just the reason. Then why show up armed? And why not just go to her place of work? In my opinion, it was to intimidate. It was to let her know we can show up to your home and shoot and kill you and your loved ones if you don’t bow down to demands. I find this is a threat and meant to intimidate.
You don’t involve people family especially. This is the article .