What was the prelude to Griffin getting shot and 6 others killed, her windows being smashed out like Hitler's?

Here is the factual prelude with no spin. The killer attended Gifford's rally months before, he did not like her answer to his question. According to HIS friends, he hated Gifford for that. He was out to get after that encounter. NOW,--what does that have to do with ANYTHING ELSE--------HE WAS INSANE----------DROP IT ALREADY