The people the guy attacked were Nazis. The are not anti-Islam activists, they are Nazis. This is not an anti-Muslim rally, this is a Nazi rally.
Shtop right there, do you have a loicense for that gigantic hyperbolic lie sir? Like serious define your view of "Nazism" for me, if I want to stretch beyond a national movement, I would say probably islamophobic or xenophobic, but then again that says nothing much, but you know what, islamophibia would have saved that cop's life in retrospect.
Because they are literally anti-Nazis. Funnily enough, they see Islam as Nazism due to Sharia being close to a lot of tenant of Islam (superiority, discrimination, etc ...), and their activity was mainly protesting anti-jihad islamization. So how is this bad again? Explain this to an ex-muslim please. Luckily there are videos showing clearly what happened so even if you want to still live in denial at least no one will believe your delusional take hopefully, and equating killing someone and stabbing with dogwhisling is absolutely nuts. I would prefer to be dogwhistled any day over getting stabbed.