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A mass attack by Israeli armoured divisions was predicted as part of the country’s response to the Hamas assault on October 7.
But instead, Israel appears to be preparing for a long war that analysts suggest could last for a year.
Israel's generals have, up to now, avoided an operation using multiple divisions to seize northern Gaza, something that would lead to high casualties on both sides.
It seems that they have decided upon a piecemeal approach using company-sized attacks heavily reliant on armour to protect their troops.
The first stage of that operation, which is aimed to seal off the northern part of the enclave and gradually encircle Gaza city, began on Saturday.
Sadr City ploy
With a news blackout in place it will be difficult to assess the progress of the operation, but the Israelis appear to have adopted a tactic used by the US during its siege of Iraq's Sadr City in 2008.
In an operation to eliminate the Mahdi Army militia by sealing off its northern Baghdad stronghold, the US used large numbers of M1 Abrams tanks alongside infantry fighting vehicles with air support, including Apache attack helicopters.
As American and coalition forces built a concrete wall along the border of the enclave, they were able to respond to insurgent fire with instant and heavy return volleys.
Footage has shown Israeli Merkava tanks accompanied by armoured personnel carriers and combat engineering vehicles entering Gaza, suggesting Israel is planning to take the same approach.
The tanks will bring instant direct firepower on to Hamas strongholds, and with all forces digitally networked, they will be able to direct artillery, armed drones and aircraft on to positions.
Furthermore, with their Trophy active protection systems, the Israeli armour will be able to instantly detect and shoot down incoming anti-tank missiles. This will make it hard for Hamas to stage ambushes.
If Israel has decided on a drawn-out campaign to retain public support and avoid international criticism, particularly from its allies in Washington, it will need to minimise both troop losses and civilian deaths.
However, the latter remains a real difficulty, with the bombing of Gaza having caused more than 8,000 deaths according to the enclave's Hamas-run Health Ministry.
The danger is well understood by Israeli politicians, who have argued that a mass attack would entail deadly urban fighting with well-prepared ambushes.
“I don’t want us to get bogged down there without achieving our goal of dismantling Hamas,” said former prime minister Naftali Bennett. “Hamas doesn’t expect this at all, it expects a ground invasion for three to six weeks.”
Hamas could be making the classic military error of trying to fight the previous war. The Israeli assaults in 2014 and 2021 were both relatively short-lived attacks measuring up to four or five weeks.
Hamas will likely have prepared for a campaign of that length, stockpiling their underground strongholds with arms, fuel and food appropriately.
But if Israel is successful in its encirclement, it will create siege conditions that could well restrict Hamas’ ability to continue fighting effectively.
However, the militants will always have the choice to continue fighting or withdraw.
“This really depends on Hamas’s willingness to fight,” said Sam Cranny-Evans, of the Royal United Services Institute think tank.
“If they dig in and go house-by-house, tunnel-by-tunnel, it's going to be a really long time, which is why the Israelis are preparing the population for that through their narrative at the moment, that this could last months, maybe a year, maybe two years.”
For this assault to be successful Israel will need to take Hamas’ extensive 500km network of tunnels, which in some places run 70 metres deep and are protected by reinforced concrete.
While Israel has specially trained units to fight underground, including unmanned ground vehicles and attack dogs, it is still highly dangerous work.
Instead, analysts believe Israeli troops will seal off tunnels they don’t need to take, either with blasts, pouring concrete or special sponge bombs, while fighting in those containing command bunkers or senior Hamas commanders.
Siege tactics could also force Hamas to the surface if they run out of fuel for generators that provide light and air underground.
“I expect [Israel's] doctrine is to just block up and move on, or fully clear those that need to be cleared,” said Mr Cranny-Evans.
Cost of retribution
Despite Israel’s fury and desire for retribution for the October 7 attacks, its leaders know that their military response has to be tempered by the price in human lives.
There are at least 220 hostages held in Gaza, used by Hamas either as human shields or as an unspoken threat to deter Israel from military action.
Furthermore, the hostages' families have grown in voice, putting pressure on the Israeli government.
But the greatest pressure on the military campaign will come from the devastation caused to Palestinians trapped in Gaza.
If the heavy aerial bombing continues and the death toll keeps rising, the US and other western powers will fear that Hezbollah and Iran could become more involved, expanding the war.
Therefore, if Israel is to fight a slow war, it may well allow more humanitarian aid into Gaza and send some of the 360,000 reservists home to stabilise its economy.
But even if it does achieve its aim of destroying Hamas, Israel requires a long-term plan to ensure that the devastation and suffering in Gaza come to an end.