Complaints about the tone of debate in the House of Commons are almost seasonal in their regularity. And they are justified. Some MPs imagine that since they lack eloquence, or the ability to articulate a rational argument, they can compensate with exhibitions of vulgarity or insult.

When tensions are high, or elections are close, the backbenches of all three parties can supply multiple examples of MPs forgetting where they are, and heedless of what is longingly referred to as “the dignity of the House of Commons.” At such times, there is almost a ritual reference to the British House of Commons and the superiority of debate in that ancient forum; the filigrees of wit and fine phrasing that mark the speeches of its members and the altogether too classy performances of its speakers.

We’re not alone in this dutiful reverence to the Mother of Parliaments. British MPs, perhaps a little slow in recognizing that self-praise is the cheapest commodity in politics, are wont to advertise their own practices and manners. Just recently, for example, there was the utterly smug and silly debate on a petition to ban Donald Trump from the U.K. The debate was spurred by Trump’s explosive campaign call for a “temporary ban on Muslims to the U.S., till we figure this all out.” But the Commons debate was more a recoil against his vulgarity — his “commonness” — especially as seen by British MPs, in contrast to their own, far-more genteel style and precious manners.

When British parliamentarians and public voices go off the rails, however, they plunge into chasms of ugliness and vilification that even Trump can’t match. Indeed, when they go low, they go really low. They go for anti-Semitism.

Take Vicki Kirby, a Labour activist whose parliamentary candidacy failed when a few of her Twitter musings fell under scrutiny. It turned out that the fresh-faced, left-wing activist had curiously ardent views on Israel and the Jewish people. Some of her more vile tweets included: “We invented Israel when saving them from Hitler, who now seems to be their teacher;” “I will never forget and I will make sure my kids teach their children how evil Israel is!;” “Hitler was the Zionist God;” and the ancient favourite of Jew-baiters everywhere, “What do you know about Jews? They’ve got big noses … lol.”

Kirby is but small fry, however, compared to Labour MP Naz Shah, the woman who ironically defeated Israel-hater George Galloway for the Bradford East constituency. Kirby’s Facebook page included the interesting suggestion that Israelis should be “transported” from Israel and relocated in the United States. All would then be peace and roses in the Middle East or, as Shah put it, “Problem solved and save you bank charges for the £3bn you (the US) transfer yearly” (no attack against the Jews is really complete without a reference to money and banks). And, in regards to a poll on “Israeli war-crimes,” she urged her Facebook myrmidons to get on it because “the Jews are rallying.” When it comes to nasty words about Jews and Israel, even Galloway doesn’t hold a candle to Shah.

But the real brick in this inverted arch of slander and slurs is former Labour MP and ex-London mayor, Ken Livingstone. During the Shah controversy, Livingstone went to bat for her by saying that Hitler was actually — dear Lord — a pioneer Zionist. According to Livingstone, when Hitler was elected in 1932, he wanted to move the Jews to Israel, and that was before “he went mad and ended up killing six million of them.” Please note the passive use of the term “ended up.”

It is appalling that 70 years after the concentration camps of the Second World War, there is a British celebrity politician hailing Hitler, one of the country’s most despised enemies, as a “Zionist.” But such are the public pronouncements of one of British politics most famous figures, a member of the Labour party’s executive committee and a former mayor of cosmopolitan London.

I think you can stack Trump up against Livingstone any day. Trump is careless, crass and heedless, but he doesn’t waltz with anti-Semitism, the most perdurable racism our world has ever known.

There are lessons that politicians around the world can take from the British Parliament and British politics. It has dignified leaders and backbenchers, speakers of grace and intellect. But when British politics slides, it finds a pit in a cavern of darkness that our side of the Atlantic, thankfully, leaves unexplored.