You didn't watch any of the videos did you? The ONLY reason why Kyle shot those guys is because they presented a very credible threat to his life. In other words they were pointing their guns at him first. He is extremely lucky that they didn't shoot first because they clearly had the advantage. One of the idiots that Kyle shot, I don't think had a gun, but he was hitting Kyle in the head with the edge of his skateboard and, yes, that then became an attempt on his life.
If you really want an objective opinion then watch the unedited videos that are out there. The ones without some news commentator blathering all over them about how evil Kyle was. Kyle acted 100% in self defense. He didn't go there to shoot people up. He went there as part of a group to offer first aid to the victims of those rioters and to help protect people's businesses from being burned down or looted.
I guess to be a good little leftist today then you have to accept that those riots and all other riots all around the country were people were murdered, injured, had their businesses looted or burned down are all perfectly acceptable. And if anyone gets in their way then those people must be prosecuted to the fullest extent of the law, especially if they are innocent.