Every metre of Gaza will present immense danger to Israel’s assault troops with the likelihood of death or injury ever present.
The soldiers for the looming attack will need every element of Israel’s sophisticated military to battle through an array of dangers, not least underground.
To complete Prime Minister Benjamin Netanyahu’s stated aim of “destroying” Hamas, the Israeli army will have to fight every step, including through the estimated 500km of tunnels.
Justin Crump, chief executive of intelligence company Sibylline, who also served in the British army in Afghanistan and Iraq, agreed. “I’ve done some tunnel fighting training and it is extremely challenging,” he said.
“You have one or two people in front and everyone else is just potentially queued up behind them waiting for a hand grenade to come around the corner.”
Hamish de Bretton Gordon, a former British army officer, said the military would have to push through Gaza, “inch by inch” with its forces facing “booby traps and ambushes everywhere they go”.
“Tunnel fighting is absolutely horrific because fighting above ground is one thing but fighting underground is entirely different,” said Col de Bretton Gordon. “There will be a lot of civilian casualties, a lot of Hamas casualties and a lot of IDF casualties too,” he added. “It’s going to be really complex and really, really difficult.”
The last time Israel attempted a military operation on anything like the same scale was the 2014 Operation Protective Edge.
Extensive air strikes on Hamas tunnels, bases and dumps were followed by a two-week ground attack that pushed just a few kilometres into Gaza where the Israelis encountered fierce resistance.
Given 2023’s uncompromising war objective, the operation is likely to last much longer.
“If the primary aim is to destroy Hamas that means clearing the tunnels, clearing everything, leaving no stone unturned, working your way through Gaza from north to south, east to west,” said Mr Crump.
“But the longer this takes the more the Gaza civilian population will be held up as martyrs.”
A change in modern warfare has seen the widespread use of drones, particularly in Ukraine.
Israel will use autonomous ground vehicles to push ahead of troops using infrared sensors and cameras to identify Hamas fighters. Some drones will carry machine guns while others will aim to disable booby-traps both above and below ground.
The Israeli army also has a battalion of specialist “tunnel warriors” who have been trained specifically to assault Hamas underground positions.
It will also use its secretive “Ghost Battalion” which has a range of capabilities and the firepower of an armed brigade.
Another option will be to identify tunnel entrances and drop thermobaric bombs to seal and kill those inside.
A major intelligence-gathering operation will be carried out before a ground assault to identify targets and obstacles using satellites and drones.
Following its failure to warn of the Hamas attacks that killed more than 1,400 people in Israel, the intelligence agencies will be aiming to track extremists’ communications to assist targeting. Human intelligence will be more difficult but Hamas prisoners might yield information as will any informants that remain in Gaza.
During the ground operation, Israel will also have to maintain a strong security line the length of the Gaza Strip to prevent any further Hamas assault on their territory,
“It would be a considerable distraction and embarrassment to the Israeli military and government if Hamas were able to infiltrate via their tunnels or use paragliders or stage an assault from the sea again,” warned Brig Ben Barry, of the IISS think tank.
By ordering civilians out of northern Gaza, Israel has essentially created a “free fire zone” in which anyone present could be viewed by Israel as a legitimate target.
To get to the tunnel entrances the infantry will need to proceed over open ground in Namer armoured personnel carriers with covering fire from Merkava tanks. Both are equipped with armour and the Trophy active protection system that can destroy incoming missiles.
The Caterpillar D9 bulldozer will also likely be utilised due to its ability to withstand heavy attacks from small arms fire and RPGs.
Israel has an estimated 100 of the 50-tonne bulldozers that are not only capable of safely detonating landmines and IEDs but can clear routes for armoured vehicles by demolishing houses. The D9s can also be remotely operated.
The rescue of the 199 hostages, some of them foreign nationals, is initially unlikely to play a major factor in the ground assault planning given the key war aim of eliminating Hamas.
However, special forces will be on standby if credible intelligence emerges on their location. The operatives will more likely move into their assault positions in Namers rather than helicopters which will prove difficult to operate safely in the combat zone.
However, there remains hope that there could be a negotiated release of the hostages.
In any campaign, commanders state that “the enemy has a vote”, and in this, Hamas will have a choice on whether to fight in northern Gaza or opt for minimal resistance.
But they will understand that by getting Israel to inflict significant destruction on the territory, it could draw in Hezbollah and Iran, and potentially America’s aircraft carriers, achieving their aim of a wider conflict.
“A military campaign to root out terrorism does not work without a wider and more comprehensive solution, in fact, it is what the terrorists want,” said Mr Crump. “And the vital ground for the Israelis is international public sentiment so they've got to do something differently to just executing a military outcome without considering the population of Gaza."
This may ultimately lead to Israel changing its war aims, he added.