(CNN) Late last week, I saw a tweet about the Census Bureau's conclusion that by 2045, groups once thought of as minorities would make up the majority of the US population. I thought it was a data point, well-known to most, that was worth repeating.

This is a coming turning point in American history that will make us culturally richer, stronger, and better prepared for the global era. It's very good news. https://t.co/g6o6V7cp3k

The hate erupted almost immediately. Someone in some alt-right Reddit discussion flagged the discussion, recasting this long-time coming demographic trend as "white genocide" and framing me as a Jew (a "globalist") promoting that genocide.

The messages contained threats, personal attacks and grotesque stereotypical images of Jews. The tweets showed yet again that Twitter does not police its site or have any standards. Some users I reported. Some I blocked. And as soon as I was done, scores more appeared.

David Rothkopf

I had probably faced only 20 or 30 such instances in my life before 2016, but I have been attacked this way thousands of times since then. Something happened in 2016 that made such attacks more acceptable. Something more than just the growth of social media that lets cowards harass their targets anonymously. That existed before.

And something more than just the "permission" that was offered these groups as Donald Trump and his ethno-nationalist movement rose to power.

Trump, his former chief strategist Stephen Bannon, senior policy adviser Stephen Miller, their Russian bot armies of supporters, and others went beyond permission: they actively encouraged the hate. They did it in Charlottesville last August, when they equated a white nationalists' hate march to the peaceful protest of those who opposed this intrusion on their city.

They did it through their immigration policies, and they did it when Trump viciously attacked Mexicans and singled out African-Americans with his transparent race-baiting

The hateful and intolerant have gained institutional support of a sort they have not had since Nazi Germany. It is not an analogy to be invoked lightly and I use it cautiously. Thirty-three members of my family were lost in the Holocaust. My father and his parents barely escaped. He showed us the yellow star he had to wear as a boy. He seldom discussed it but periodically he would write us notes describing the fate of my relatives killed in the camps.

JUST WATCHED Schwarzenegger writes a speech for Trump Replay More Videos ... MUST WATCH Schwarzenegger writes a speech for Trump 00:53

One time, when I was a kid, when some local idiots drew a swastika on our driveway, I could see how shaken he was. He was a strong guy. An artillery officer from World War II. He did not fear much. But I think he always saw the possibility that this kind of hate would re-emerge.

It has. We see it now across Europe -- in Russia, in Poland, in Hungry, and with the rise of ethno-nationalists across the EU. It is fostered by the Russians as they seek to divide our societies. But they are abetted by the alt-right everywhere.

Perhaps the worst of these haters are just a tiny fraction of society. But large segments of the population have embraced them by degrees because they express their political views. And even larger segments remain silent.

So, empowered, enabled by technologies that amplify their message and make their hate easier to disseminate, they are -- to borrow a phrase with a long history -- poisoning the wellsprings of democracy. And distressingly, as our President becomes more desperate, he seems more inclined to further embrace them; to ratify some Americans' fears of coming changes, to abuse his power to empower, and institutionalize their ideas.

JUST WATCHED Is hate on the rise in America? Replay More Videos ... MUST WATCH Is hate on the rise in America? 02:09

Race-hatred and prejudice are not new in America. We have institutionalized racism before -- with slavery, through segregation, through voter suppression, and in a thousand other ways.

And now we are doing it a new way and at the center of it, the leader of the new movement is Donald Trump, abetted by all those around him who have used his power to gain some for themselves. By John Kelly -- who was an architect of the refugee ban.

By Miller and Bannon, of course, but by every member of the Cabinet and staff who tolerates this, who does not call it out, who plays to the subtle divisions, who uses the hate to fuel their own ambition. There was no excuse to remain part of this post-Charlottesville.

In fact, the only healthy and humane response is to seek the removal of Trump, the end of this era and the restoration of the values of decency and tolerance that have long been the American ideal.

We must begin by recognizing that what we are seeing is not just greed or incompetence or stupidity or corruption at the top. This is something much more pernicious. Stopping Trump, those who have allied themselves with him and the hate-mongers he has embraced is not about simple politics. It is about the salvation of the idea of America.