But some things really are just plain-old, gratuitous Jew hatred. Like saying that Zionists operated the Nazi concentration camps. That’s some serious old-school anti-Semitism, right there.

And that’s precisely what “media communications expert and volunteer pro-Palestinian activist” Greta Berlin, co-founder of The Free Gaza Movement (best known for its backing of the Gaza flotillas), tweeted out into cyberspace via Free Gaza’s Twitter account on Monday: “Zionists operated the concentration camps and helped murder millions of innocent Jews,” read the tweet, and it was followed by a link to a grossly anti-Semitic video which, among many other things, asserts the following:

And of course Hitler, allying himself with the Zionists, he said, 'After all, you're right.' He said, 'We have the same goals.'  And so he allied with the Zionist Party and the mission of the Nazis was to force the anti-Zionist Jews to accept Zionism.  And this is what the concentration camps were about.

In the meantime, Berlin has provided the Mother of all non-apology apologies, saying that (a) she thought she was only sharing the link with her Facebook friends and is sorry for the mix-up and that furthermore, (b) she hadn’t even watched the thing herself when she shared it. She was just in a rush, you see, and: Oopsie!

Due respect (of which none is due, but whatever), but if you disseminate something entitled “Zionists operated the concentration camps and helped murder millions of innocent Jews,” I’m not much mollified by the fact that you meant it to be a private act. I reject that same miserable excuse whenever it’s offered with regards to racist emails about President Obama; I am most certainly not going to accept it when the statement in question accuses Jews of serving as Hitler’s butchers. One would think that a media communications expert might be able to suss that out on her own. Apparently not.

So as a Jew, a Zionist, and an Israeli, I’m offended and disturbed; as a pro-Palestinian activist, I’m pretty pissed off.

I’ve spent the last quarter of a century advocating for a two-state peace, because I believe it to be in Israel’s best interests and a moral imperative for the Palestinian people. I’m hardly alone in this (as the existence of groups like J Street and Peace Now and Breaking the Silence and the Israeli-Palestinian Bereaved Families Forum proves), and though the fight has become particularly painful in recent years, we two-state-supporting Jews carry on.

And we are forever being accused of self-loathing. And treason. And naiveté. And general, all-purpose, delusion. And, of course: anti-Semitism. Because once you say that you think Palestinians have rights too, there are always one or two folks willing to toss you out of the Jewish community all together.

I know people involved with some of the various organizations that overlap with The Free Gaza Movement and Gaza flotillas. I know them to be good, upstanding people who often disagree with me on the efficacy of a two-state solution and/or nationalism as an organizing principle. They’re devoted to the furtherance of human rights for all humans, and firmly opposed to the use of violence as a tool to further any end. They’re the living, breathing proof that one can oppose Israeli policies without hating Jews; that, in fact, insisting on a direct correlation is absurd.

But then along comes a Greta Berlin—an unreconstructed, unapologetic, old-fashioned anti-Semite of the kind that once cheered as Jews were thrown down wells and into gas chambers. And—whoosh!—those of us working to advance Palestinian rights are back on our heels, forced to disassociate and distance ourselves from the illness that she spreads; the morality of our cause (not to mention the actual, and rather urgent, needs of the Palestinian people) tarred with the brush of her hate, and thus easily dismissed.

When international leaders such as Mahmoud Ahmadinejad talk this way, Israel and the Jewish community rightly show concern and take caution, but I don’t believe that the Middle East’s most powerful state is threatened by the rantings of one twisted woman, nor by anyone in the various pro-Palestinian nonprofits who may share her nauseating views (and yes, I know she’s not alone).

What is directly threatened by the anti-Semitism of a handful of so-called “pro-Palestinian activists” is the cause that many good people have spent years fighting for: A just resolution of the Israeli-Palestinian conflict.

The Greta Berlins of the world must be called out, not just by Jews, but by all people genuinely dedicated to human rights and conflict resolution. Their hatred is vile, their desecration of Hitler’s victims inexcusable—and with their every utterance, they make a just peace and regional stability that much more distant.

This isn’t a Jewish issue, it’s a human issue. And the humans who happen to be Palestinians would be much better off without this kind of help.