We all know this attacker is a reflection of white people and "white culture," in the same way that a Muslim or African American represents their entire group.
I kinda figured that was the angle you were going for with this. Which is fine btw...you're trying to highlight a social double-standard that has a certain measure of prevalence.
However, like I mentioned before (as you and I have had this conversation numerous times), one has to also realize that there's a logical fallacy going in the other direction as well.
Obviously, neither logical fallacy is right, and one doesn't justify the usage of the other...
On these "shooting: lone wolf vs. represents the group" threads, one side demonstrates a double standard that "when it's someone from my group, it's a lone wolf, when it's from that 'other' group, it represents the lot" (which is the one you're trying to highlight...which you're right, that's an unfair double standard).
However, the logical fallacy that the other side of the coin poses is one of the "false equivalency" variety where they portray it as a pure apples-to-apples comparison when it's in fact not.
Firstly, the "Muslim or African American" side that you're comparing to "White" is an incorrect comparison... Black to White would be a valid comparison to look at, however, those are races, where "Muslim" represents an ideology. It's a circumstance of birth vs. a circumstance of choice...big difference there.
As it relates to the "group association in the public eye" mentality that occurs when the suspect is Muslim, as opposed to the "lone wolf in the public eye" mentality when it's a Christian, one has to be honest in acknowledging that, even though the double-standard still isn't fair, it exists due to the prevalence, frequency, and magnitude of the events.
We has humans are naturally wired up to be perceptive to pattern detection. It's the reason why if a little kid has been bitten by 3 different dogs recently but never bitten by a cat, he'll be more skittish around a random dog than he would be around a random cat (even though the random cat may be just as likely to bite him as that random dog). Humans are also very perceptive to probabilities as well. If a person goes to a neighborhood 10 times and of those 10, 3 times their car was broken into, they're going to have greater concern over going to that neighborhood vs. a neighborhood where it's never been broken into (even if they've never been to that 2nd neighborhood before). Magnitude is a no brainer...a match and an acetylene torch can both burn you, however, an accident with one can be devastating compared to an accident with the other, so people are going to exercise caution at different levels as a result of that
So, as that ties in with the attributes I mentioned before (prevalence, frequency, magnitude), each of those ties in with the human thought process on whether something is a random, somewhat unlikely event, verses something that's part of a larger pattern. That's the reason why, even though "radical Christianity" and "radical Islam" are both horrible ideologies that have both used violence, people are far more worried about the latter. When you have big, high profile events, happening in what seems like short succession, people are going to start seeing that as a pattern and looking for common threads, as to where if the events are much smaller scale and occur once a decade or less, peoples' "pattern detection engines" aren't going to rev up as much.
It's the main reason why the standard "oh, well anti-abortion Christian extremists have blown up clinics before, why aren't you as worried about that????" argument falls flat in most cases. They aren't racking up 10+ kills at a time in events that are less than year apart, they're not causing so much unrest in parts of the world that they're causing mass migration (I don't see a line at the Canadian border of people trying to escape out of fear of the militant Christian groups in Tennessee coming after them).
So while I'll agree that the double standard isn't technically "fair", to pretend that we don't understand the real reasons why the double standard exists, and merely try attribute it to bigotry, is intellectually dishonest and doesn't do much to promote a real change in thinking. It doesn't put the one side's fears at easy, and doesn't give other side any credibility in their opinions. They're simply going to see the other side as "the people who call me a bigot for being legitimately worried about something"
The fact of the matter is, the religion of Islam has a lot of problems at the moment, problems that exists with a prevalence and scale that simply isn't being seen in other world religions at the moment.
I don't think a person has to take one side or the other on the matter, I think a reasonable person can both acknowledge that fact, while also saying that it's wrong to judge people by their group association, simultaneously.