Until May of last year, I was known, or in truth barely known, as a lifelong anti-racism activist, trainer, teacher, writer, and lecturer.

As a young woman, I was active in the boycott movement against the apartheid of South Africa.

It was a logical progression to become a supporter of Palestinian rights, a critic of Israeli policy towards Palestinians, and a supporter of the movement to boycott Israeli products - the Boycott, Divestment, Sanctions (BDS) movement, as well as a member of the Palestine Solidarity Campaign, Jews for Justice for Palestinians and Free Speech on Israel - a mostly Jewish group.

My nastier critics suggest my claim to Jewish identity is some kind of a defence against being accused of being an anti-Semite. It is not, it simply puts recent events into a context.

If you criticise Israel it doesn't matter who you are, you will be accused of anti-Semitism Jackie Walker

If you criticise Israel, it doesn't matter who you are, you will be accused of anti-Semitism. So, do I hate Jews? Of course not. What I hate is the far right and the pernicious effect that Israel, led by a Netanyahu government, is having on Middle Eastern and global politics.

So, how did this witch-hunt against me start?

In February last year, a group called the Israel Advocacy Movement went fishing into my private Facebook account.

I remain unclear as to when or how I became identified as a threat to Israel, though I presume I was selected as a prominent supporter of Jeremy Corbyn when it was decided his leadership was a threat to Israeli interests.

It was not a public posting, but part of a private discussion with a Zionist Israeli friend and others about the African Holocaust and the fact that Jews - notably my own Portuguese Jewish ancestors whose history I had researched - had been involved in the sugar and slave trade.

This Facebook contribution was reduced to a sensationalist and inaccurate article in the Jewish Chronicle which claimed that I had said that "Jews caused the African Holocaust". This is where it gets unclear. Either the Israel Advocacy Movement, or the Jewish Chronicle, reported me to the Labour Party, which then suspended me for being an alleged racist - to be specific, an anti-Semite.

I was investigated in detail by the Labour Party. My Facebook posts, my public statements were examined in detail. I attended a full hearing, but the Compliance Unit of the Labour Party could find no case to answer. Never mind, verdicts apparently make no difference. Harassment continued. The right-wing of the Labour Party, the Jewish Chronicle and the Jewish Board of Deputies appeared enraged.

READ MORE: Everything you need to know about the BDS movement

The mainstream media, including all the national newspapers, even those traditionally identified as more liberal, such as The Guardian, chimed in. No one interviewed me or asked for my version of events. They simply repeated the inaccurate, substandard and biased reporting of the Jewish Chronicle.

The British media appear to have become lazy and scared.

As Shai Masot, the Israeli official filmed undercover by Al Jazeera Investigations points out, I became someone whose every movement was to be followed and reported on.

Attempts to 'smear' Corbyn

Individuals and groups, such as Palestine solidarity groups, who wanted to hear me speak had their email and Facebook accounts hacked.

Some had to close Facebook pages to comments because of the level of racist abuse against me. Individuals have been smeared for being photographed with me, for daring to support me.

Jeremy Corbyn has opposed racism, war, has protested against injustice and oppression all his life, but this has been no safeguard against charges of anti-Semitism against him. The Labour leadership, the Corbyn revolution, whatever you want to call it, is the greatest challenge to the established political order the UK has seen for some time.

Attempts to smear Corbyn started as soon as he became a leadership candidate. Newspapers that had published anti-Semitic articles on Ed Miliband, the previous (and Jewish) leader of the Labour Party, suddenly became champions against anti-Semitism.

The mainstream media strained the limits of every story, twisting every statement, misquoting what they could, to paint Corbyn as an anti-Semite or soft on anti-Semitism. And the right of the Labour Party did what they could to assist them.

These accusations not only weaponised anti-Semitism, they also became a weapon of political mass destruction and, like all nuclear options, entailed collateral damage, not just to Labour, or the Labour movement but to pro-Palestinian and anti-war groups, to individuals, their families and friends and the political communities they were part of.

OPINION: Anti-Zionism and anti-Semitism in British politics

Being a racist is not about missing off a word in a Facebook post, it's not about getting a date wrong or calling some dubious politician a "friend" in an attempt at finding agreement.

No longer are racists people who demand migrants to be deported, who want to exclude refugees. Racists are not even the people who complain of a TV reporter wearing a headscarf. No, it's the left we are told, who are the culprits in this new racism, this new anti-Semitism.

Opposition to a Jewish state is, and remains, a legitimate, honourable political position and one that many, including many Jews, have stood by for decades Jackie Walker

The Israeli government has allocated millions to fund undisclosed activities to undermine the BDS. The fight against BDS is being led by Israel's minister of strategic affairs. Israel has hired workers whose names are classified. There is an intelligence section run by a former security services operatives that receives assistance from "a special unit" within Israeli military intelligence, as well as the secret police.

Individuals and groups are targeted and they have had some success. For example, in France BDS has been ruled as an activity that "discriminates", therefore making it functionally illegal.

I suggest attempts are being made to do the same in Britain. For example, in November last year, Tom Watson, deputy leader of the Labour Party, at a Labour Friends of Israel dinner, called out supporters of the boycott movement as "immoral".

First, principles: I oppose all forms of racism, including anti-Semitism, but I will not be silenced on criticism of the Israeli government. I agree, Zionism should not be used as abuse or a cover for attacking Jewish people. However, Zionism is part of the political lexicon, essential to challenging the concept of a Jewish state.

And let me reiterate, opposition to a Jewish state is, and remains a legitimate, honourable political position, and one that many, including many Jews, have stood by for decades.

The Lobby is available to watch online.

Jackie Walker is an anti-racism activist, trainer, teacher, writer and lecturer.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.