In Britain, protest is no longer a right. Instead, it is a privilege that is granted – or withheld – at the whim of those in power. This is the implication of new rules that the Labour government is proposing, which would dictate the time and place that protests are permitted to occur, and carry the risk of prison time for those who defy orders. Successive governments had already chipped away at this right: the last Conservative administration granted the police sweeping new powers, which the United Nations’ human rights chief condemned as “serious and undue restrictions” on democratic freedoms. Taken together, these incremental assaults on freedom have effectively abolished the hard-won right to freedom of protest.

The latest assault is justified by last week’s heinous antisemitic attack on a mosque in Manchester. There should be universal agreement that the security of British Jews must be protected. Using this atrocity as a justification to throttle dissent is not only unrelated to that duty, but perverts it. Consider Britain’s history of protest and direct action against racism and fascism, from the battle of Cable Street in 1936, to postwar Jewish anti-fascist movements such as the 43 or 62 Group, or the mobilisations against the National Front in the 1970s. Many of these protesters were derided as extremists in their day, even while they were fighting for the rights of minorities.

In today’s upside-down world, here’s what is actually going on. Israel – a foreign state – is committing genocide. Its war crimes have led the international criminal court to issue arrest warrants against Benjamin Netanyahu and his former defence minister. Public opinion in the west has turned sharply against Israel’s violence. In Britain, a large majority of people believe Israel has likely committed war crimes. Most people would back a total ban on arms sales to the state, and support the arrest of Netanyahu.

Having long since lost the argument, Israel’s cheerleaders are now seizing on a vile antisemitic crime to try to silence a mass movement against a moral catastrophe. The British government are included in this. Ministers have failed to impose large-scale sanctions on Israel, and have allowed arms exports to continue. As the US author Ta-Nehisi Coates recently said of the Democrats, “if you can’t draw the line at genocide, you probably can’t draw the line at democracy”. The same applies to the Labour government.

People who are protesting against the erasure of Gaza have been deemed hateful extremists. But there is a reason that there hasn’t been a more extensive crackdown on these protesters before now. The former cabinet minister Penny Mordaunt recently claimed that demonstrators were calling for “death to Jews”, but the reality is that so few protesters have made hateful (and thus illegal) statements about Jews that the police have had no reason to crack down on them. Meanwhile, Jewish protesters marching for Palestinian lives have been slandered. After one such protester told the BBC that he had joined every protest for the last two years, Ben Houchen, a non-Jewish Tory Lord, called him a “useful idiot”.

Collapsing Jewish identity into the actions of the Israeli state is not only cynical, it is dangerous. The International Holocaust Remembrance Alliance definition of antisemitism, adopted by the British government and many other institutions, has been rightly challenged for stifling critique of Israel. But there should be no controversy over one of its examples: that “holding Jews collectively responsible for actions of the state of Israel” is antisemitic. Despite this, Israel’s defenders have repeatedly attempted to conflate criticisms of Israel with antisemitic attacks on all Jewish communities, regardless of what many Jewish people make of these actions.

This is why we’re now at a point where the Metropolitan police can suggest that protests opposing Israel’s crimes should be called off on the basis that they could “inadvertently or deliberately” endorse antisemitism, and why why Priti Patel, the Conservative shadow foreign secretary, has declared that Labour’s belated recognition of Palestinian statehood had rendered the party “complicit in the appalling abuse we see across our streets and across Britain’s Jewish community”.

On the same day as the synagogue attack, the Israeli army killed at least 57 Palestinians in Gaza – another hideous tally in two years of daily atrocities that have left tens of thousands dead. British politicians and media outlets have barely concealed the lack of value they attach to Palestinian life. It is among the most brazen expressions of racism of our time. One wonders how history will judge this moment: politicians are accusing people who are protesting against genocide of inciting hatred, while they are supporting those who are committing genocide.

Our government has already crossed a dangerous threshold by proscribing Palestine Action, a non-violent, anti-genocide direct action group. More than 2,000 British protesters have been arrested, mostly for holding placards opposing genocide and supporting the banned organisation. Many of them are pensioners; one is a retired priest, another the daughter of a Holocaust survivor. When the state begins calling movements “terrorism” when they are nothing of the sort, it is attacking democracy itself.

It’s not hard to see where this all leads. In the US, Democrats helped to demonise pro-Palestinian protests: the former house speaker Nancy Pelosi suggested that some were “connected to Russia”, while Joe Biden called such protests antisemitic. In doing so, they only helped to legitimise the authoritarian crackdown on such protests – and on freedom of expression in general – under Donald Trump. If Nigel Farage becomes prime minister, a hard-right government would be granted sweeping powers to control dissent. What do you think a Reform government would do with this repressive toolkit? Our ancestors struggled, suffered and died to secure our freedoms. We will come to rue how casually we let them go.

• Owen Jones is a Guardian columnist

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