Because the left commits more violent acts (and is much more tolerant of violence) by FAR than the right. Roughly twice as likely from this poll, but I've seen much higher numbers thrown about. https://www.newsweek.com/charlie-kirk-shooting-poll-democrats-2128761#:~:text=A%20YouGov%20poll%20conducted%20on%20September%2011%20among,they%20oppose%2C%20compared%20to%206%20percent%20of%20Republicans.