On the off-chance the shooting wasn’t what it looked like, I reached out to people who knew the gunman, 29-year-old Joshua Jahn. Three who knew him since at least middle school agreed to speak to me on the condition that I not name them, corroborating their friendship with photos and other records. Their accounts paint the picture of someone with a vaguely libertarian bent who despised both major parties and politicians generally (including Trump) but who didn’t engage with politics beyond that. He preferred edgy humor, video games and the message board 4chan, all of which he became increasingly steeped in as he withdrew from social life as well as their own friendships several years ago, they said.

None of his former friends believed that the “ANTI-ICE” inscription could possibly be sincere, feeling such a serious political statement was anathema to who Jahn was. His humor was deeply ironic, often offensive and aggressive to the point of alienation.

“He was most certainly an edgelord, an irony guy,” one friend said. (Edgelord is online-speak for someone who likes to espouse edgy, nihilistic views). Asked about the inscription on the bullet, the friend said: “Josh was an edgelord who wanted someone to get blamed. I think he tried his best to write something goofy … to rile people up.”
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That said, one friend recalled that when Trump first came to power, Jahn “was not a fan” — though he had contempt for mainstream politicians in general. His friends say he had more of a libertarian bent, with one recalling an interest in the libertarian figure Ron Paul.

https://www.kenklippenstein.com/p/the-ice-shooters-motive