Couple of weeks back a Caucasian Republican tried to assassinate Trump. That isn't even news now. If it was an immigrant or a Muslim that did that, it would still be front page news and debated on all news including liberal ones.
In this horrific attack, if the attacker turns out to be an immigrant or a Muslim we can be sure it will be a talking point for some time to come.
Why does it matter more who committed the crime? Does it make any difference to the victims or their families? Does it make any difference to the average citizen?