Last week in Cairo, Hedy Epstein, a frail 85-year-old American woman, embarked on a hunger strike for the first time in her life to protest the ongoing blockade of Gaza. She has no idea how her body will hold up, she says, but that isn't her priority. She is one of more than 1,300 international participants from 42 countries who flew to Cairo with the aim of participating in the Gaza Freedom March, initially planned to coincide with the first anniversary of Israel's Operation Cast Lead. Many of these committed individuals of all hues and religions are elderly; all have dug deep into their pockets to pay for their own flights and hotels.

They had hoped to spend one day in the Egyptian capital before marching into the Gaza Strip through the Rafah crossing in solidarity with the 1.5 million besieged residents. It transpired that only 100 Americans were given the green light after discussions with Egypt's First Lady Suzanne Mubarak, but just 84 took up the offer. The rest — Epstein among them felt that the group should not be split up and chose instead to continue her protest in Cairo.

Besides being a rare woman of substance willing to transcend the restrictions imposed by her advanced age for a cause, Epstein is remarkable. She is a Jewish Holocaust survivor who lost her entire family to the horrors of Auschwitz. The last communication that she ever received from her mother was a postcard dated September 4, 1942, that read: "Travelling to the east … Sending you a final goodbye."

She has dedicated her life to civil and human-rights issues, which she highlights through articles, books and public speaking. Her tragic experience has given her an insight into the suffering of others, irrespective of their beliefs. Since 2003, she has made five visits to the occupied West Bank to demonstrate against Israel's crimes.

Cofounder of the march's organisers, Code Pink, author and recipient of a collective Nobel Peace Prize, Medea Benjamin, who the Los Angeles Times has called "one of the high profile leaders of the Peace Movement," was also in Cairo championing an end to the Israeli-imposed siege.

Medea has characterised herself as "a nice Jewish girl from Long Island", but given her controversial views it's probable that many of her compatriots and fellow Jews would take issue with "nice". She has described America's ‘war on terror' as a form of terrorism launched in "a spirit of revenge" and has urged her fellow Americans to examine the reasons behind anti-Americanism in the Arab world. She has visited Gaza to show support three times since Israel's onslaught last winter.

Yet another concerned Jew who has joined the Gaza Freedom March is former South African politician Ronnie Kasrils, whose grandparents fled Czarist pogroms. Kasrils courted controversy when he authored A Declaration of Conscience by South Africans of Jewish Descent in 2001 and later wrote an essay titled David and Goliath: Who's who in the Middle East, which likened the Israeli government to "baby killers".

Also among the protesters were several rabbis, among them the founder of the Shomer Shalom Institute for Jewish nonviolence Lynne Gottlieb, who said she made the visit "to bring more Jewish people into the circle of resistance".

All those who stepped out of their comfort zones during the holidays to support the people of Gaza should be commended. But Epstein, Benjamin, Kasrils and Gottlieb, along with the other Jews who joined the march, have exemplified humanity's best; people willing to prove the courage of their convictions even if this means encountering hostility from their own communities. Indeed, a Paris bookshop owned by the Jewish leader of the 300-strong French delegation, Olivia Zemor, was attacked last summer by thugs announcing that they were members of the Jewish Defence League.

Jewish intellectuals have been spearheading the peace movement for decades; notably, the late Nobel Literature Prize recipient British playwright Harold Pinter, the American political scientist Norman Finkelstein, the British writer and professor Tony Judt, and the widely respected linguist turned activist Noam Chomsky. In 2008, 100 prominent British Jews wrote to The Guardian saying they could not celebrate the birthday of an Israeli state founded on terrorism and ethnic cleansing.

A growing number of Israelis feel uncomfortable too. Columnist Larry Derfner who writes for The Jerusalem Post says Israelis need to ask themselves a hitherto taboo question: "If anybody treated us like we are treating the people in Gaza, what would we do? We have to dare to put ourselves in those people's place," he writes. "And we have to stop doing to them what we would never allow anyone to do to us. Otherwise, we Israelis have no conscience, and little by little we become capable of anything."

Unless Israel changes its vicious tactics and genuinely engages in the pursuit of peace, given enough rope it will hang itself. The self-declared Jewish state cannot survive without the support of world Jewry, which for a variety of reasons not least its brutality towards a helpless people struggling to survive under occupation is fading fast.