The theme of Holocaust Memorial Day this year is Fragility of Freedom - the freedom to be who you are without fear.
A freedom which, Laura Marks, chair of the Holocaust Memorial Trust, says is "being eroded... on a macro level".
"It's a fundamental freedom to be Jewish or Muslim. Once those freedoms get eroded because you're too afraid maybe to be who you are, we're on a slippery slope," she told Sky News.
"Hatred towards faith communities at the moment is very frightening and dangerous," she said. "It's important every year to remember how the world can go crazy when we let hatred get out of hand."
It was a sentiment echoed by speakers throughout today's Holocaust Memorial Ceremony at the Guildhall in London.
In his recorded video address, the prime minister was frank: "I want to address very directly the despicable resurgence of antisemitism. Because it is not enough to come together today and faithfully remember the Holocaust.
"We must also act on what that memory teaches us. It is sickening that Jewish people are once again facing the most abhorrent antisemitism in this country."
The chief rabbi also said: "Antisemitic attacks are not only a thing of the past. Precious and hard-won freedom must always be accompanied by responsibility."
This year's memorial events come against a backdrop of rising antisemitism and Islamophobia. In October, following Hamas's attack against Israel, police in London reported a 1,353% rise in antisemitic offences.
Last weekend counter-terror police in London said they'd seen an "unprecedented" rise in the threat from terrorism following the latest conflict in the Middle East, which they say has become a "radicalisation moment".
Ms Marks told Sky News there has been a "blaming of communities" here in the UK for things that are "way out of our hands".
She added: "On Holocaust Memorial Day we really try and bring people together."
And they did just that. Survivors of the Holocaust and subsequent genocides gave powerful testimonies, sharing their experiences and accounts.
"It is a landmarking memory I don't think we should forget," Peter Lantos said.
He was deported to a Nazi concentration camp when he was just five years old. Mr Lantos and his mother both survived but his father died of starvation.
Mr Lantos added: "I did see sights which were incomprehensible. People dying and dead. At the beginning, they tried to bury or burn them.
"But so many people died in such a short time that the corpses were left lying around."
The message from politicians and faith leaders here today is "never again".