This idea keeps coming up again and again that using the word 'racist' in the context of the Trump campaign is essentially name-calling, an insult.
The problem is, racism is a big, big, big issue. And Trump is a racist bigot, you simply cannot deny it. That's why people that are described as 'on the left' feel so strongly about him. It's not 'pulling the race card', it's an actual big problem. America has spent 200 years trying to overcome it, and it's still so far behind. The open racism displayed by Trump is the reason why so many people viscerally hate him. Add to it the sexism (and sexual assault), the bullying, and the xenophobia, and the support for him becomes essentially unfathomable for many who consider his attitudes and behaviors completely incompatible with basic democratic values.
The article posted calls it smug, the commuter above called it 'not tolerating dissent'. I would call it a zero tolerance policy on racism, sexism, bullying and xenophobia.