A thick crust of black ash has settled on the pavements and roads in the centre of Jenin.

It comes from barricades of burning tyres set up by young Palestinian men, who prowl streets where they might see an Israeli jeep. Some of them carry rocks or small home-made bombs to hurl at passing Israeli vehicles. In sporadic bursts, gunfire and explosions echo in the refugee camp, which is on high ground above the town centre. Israeli drones buzz constantly overhead.

At times, armed Palestinians emerge from the tyre smoke to fire at the Israelis.

Violence between Palestinians and Israelis has become almost a daily event this year. When blood is spilt there is often a dynamic of retaliation, that includes Palestinian armed groups, Jews who live in settlements in the occupied West Bank that are illegal under international law, and the Israeli army. The Israelis said they moved in on the Jenin camp because more than 50 relatively recent attacks were launched from there.

But the roots of violence, despair and hatred go much deeper than the latest violent confrontations. They thrive in the poison generated by a conflict over possession of the land that started more than a century ago. For a while, back in the 1990s, there were hopes that peace might come if an independent Palestinian state could be established alongside Israel, the so-called two-state solution. The attempt failed.

Powerful Western countries, including the US, European Union members and the UK still insist that two states are the only possible solution. Their words are empty slogans. The last American attempt to try to make the idea work collapsed in 2014.

The Israeli operation here in Jenin was in the air for months. Despite regular smaller Israeli raids, Palestinian armed groups had become strong enough and united enough to control the Jenin refugee camp. They seemed to be getting stronger.

A fortnight ago they blew up an Israeli jeep and fought hard to repel an Israeli raid, in which the Palestinian dead included a 15-year-old girl. The next day four Israelis were killed by two Palestinians who burst into a restaurant not far from Jenin, where they were eating. The Israeli army protected Jewish settlers who rampaged through Palestinian villages burning cars and houses, in a series of reprisals.

It was a matter of time before the Israeli army moved against the Palestinians who controlled Jenin refugee camp. It says it is carrying out a systematic operation to track down and destroy weapons and explosives.

Fury and frustration rage through young Palestinian men who have gathered in angry knots at road junctions in the town and outside a hospital on the edge of the Jenin refugee camp. Their barricades of burning tyres leave behind black circles and piles of burnt rubber and twisted wire.

The Israeli army is releasing updates on explosives discovered and neutralised in the two days it has been in the camp, along with what it calls terrorist command centres. The business-like tone of the military communiques contrasts with the statements made by members of the Israeli cabinet who oppose any kind of Palestinian self-determination.

After a Palestinian was shot dead in Tel Aviv by a passer-by, after he had rammed his car into a crowd of Israelis, public security minister Itamar Ben Gvir issued a statement saying Israel's war in Jenin was also their war in Tel Aviv. Every Jew, he said, was a target for murderers.

Mr Ben Gvir and his political allies have been pressing for a punitive sweep through the West Bank to deal with their enemies. The Israeli army is more cautious, as it is more worried about the risks and consequences of escalation. All the indications are the Israeli army would like to restrict its operation to the Jenin refugee camp, declare victory soon and order its soldiers back to their bases.

Israeli victories after an operation like this never last long. Palestinian armed groups restock their armouries and the cycle begins again. Plans to expand settlements for Jews on occupied land that Palestinians want for a state, sometimes called a Zionist response by Israeli politicians, also raise the temperature.

Many Palestinians are disenchanted with their own ageing and ineffective leaders in the Palestinian Authority, a legacy of the 1990s peace process that was supposed back then to build the institutions necessary to create their own state.

When this operation ends, on past form both sides will claim victory. Then the current realities of this long conflict will reassert themselves. Anger, despair and poverty will reinforce the culture of resistance that has embedded itself in Palestinian society, especially here in Jenin and in Nablus. And Israel's right-wing, hyper-nationalist government, as long as it lasts, will try to match its rhetoric with action.

The real danger is that Israelis and Palestinians are sliding into an even more violent phase of their long conflict.