Last week, at the height of Operation Cast Lead, a group of Israeli firemen threw their hats into the political ring, albeit in somewhat undiplomatic and uncivilised fashion. During a peaceful anti-war vigil outside a Tel Aviv air force base, several members of the fire brigade turned on one protester, drenching her relentlessly with water from their hoses, before approaching her and ordering her into the station in order to "give us all head".

Their actions were, while wholly illegal, none the less emblematic of a massive shift in Israeli public opinion over the last few years, according to Sharon Dolev, the woman on the receiving end of the assault. A veteran activist, Dolev has suffered a great deal during her 20 years of campaigning in the Israeli peace camp ("death threats, being shot with rubber bullets, hate mail, beatings"), but said that this incident was "the first time that the establishment felt safe in [taking action such as this]".

"It used to be a big deal if bus drivers criticised protests and vigils in public," she recalls, "since as employees of the state, they were not allowed to express political opinions in uniform." Now, however, the firemen felt so secure of escaping punishment that they even bombarded her with firecrackers during the attack, telling her "now you know what it's like to live in Sderot".

When video evidence emerged on an Israeli news website of her ordeal, readers' comments were predictably scathing of Dolev and her fellow protestors for daring to speak out in the first place against the IDF's operation. "Of the 380 comments, all but 10 were in support of the fire brigade," said Dolev. "Some readers even called openly for our murder, urging the police to shoot us, or saying 'Why use water – use acid instead'."

In her view, the inexorable shift of the Israeli public towards out and out hostility and hyper-defensiveness was inevitable from as far back as 1967, when the West Bank was first conquered. "We used to hold signs at protests reading 'The occupation will corrupt'," she told me. "Now, we can see that it has [come to pass]. As a society, we have lost our ability to see clearly; we have let fear blind us. Once, calling someone a racist was the harshest accusation you could make. Later, you began to hear people say 'I know I'm a racist, but...'; nowadays [during Cast Lead], we heard 'I know I'm talking like a Nazi, but at least the Nazis knew how to deal with their enemies'."

Despite others employing Nazi comparisons to describe Israeli military actions, Dolev isn't comfortable with such terminology herself, not least because it derails the debate about the issues at hand. "It's all too easy for the Israeli authorities to say 'we didn't build an Auschwitz for the Palestinians, so everything's ok', but in reality everything is not ok." She believes that history has come full circle, and that instead of learning the lessons of the Holocaust, "we have become the racists ourselves".

"Isn't Gaza a ghetto?" she continues. "OK, we don't use the Palestinians' hair for cushions, but the [stage is being set for the] same kind of process of dehumanisation here." Working in a joint Israeli-Palestinian organisation in Gaza in 1989 gave Dolev her first exposure to "the banality of evil", she says. "It wasn't seeing a soldier get scared and shoot into a crowd, but rather seeing a girl sitting in her house and getting shot by a stray bullet. And then, when she needed to be transferred to a Cairo hospital, the Shabak officers saying only she could cross, and no one else. A 12-year-old girl, in a vegetative state, and they wouldn't even let her mother accompany her. That is the banality of evil."

In her eyes, the Israeli public has allowed its leaders and military to get away with such punitive measures simply because they have allowed fear to override all other emotions: "Fear turns us into beasts," she says flatly. "I remember in my first week at school, aged six, we were taught how to blockade the classroom in case a terrorist got into the playground. While some fear is justified, there is not enough reason to make the public terrified on a daily basis." The media are just as responsible as the government for perpetually scaring ordinary Israelis, she believes. "Fear sells papers," she says cynically.

Such defensiveness allowed the police to get away with imprisoning some 700 activists over the course of Operation Cast Lead, she believes; many on the most spurious of charges. "They arrested some on the charge of disturbing public order, others on even vaguer charges. And some were even detained for 'damaging the nation's morale' – a charge which doesn't even exist [in the statutes]. There is no law in Israel anymore."

As well as her experience at the hands of the fire brigade, Dolev also points to the kind of sloganeering in the election campaign as proof that the bedrock of democracy on which Israel is founded is beginning to look far less solid. "When you have Lieberman declaring 'No loyalty, no citizenship', you start to worry about what point we've come to." However, she is undeterred in her struggle on behalf of the peace camp, believing that hope is not lost in terms of convincing the Israeli public of an alternative to perpetual war and aggression. A firm promoter of the Arab Peace Initiative, she is convinced that the proposal is the best way to resolve the decades-old conflict.

"It's the biggest carrot ever offered to the Israeli people," she says. "One-state or two-state is a non-issue; whatever the two peoples agree on I would take with both hands. All that matters is that there are borders, and that those living within the borders are given full rights and citizenship. However, I worry about [Israeli Jews] becoming a minority, because after all we've taught them over 60 years of how to treat minorities, it's become dangerous to be a minority ourselves ... "