"We are in a tough war," Israeli Prime Minister Benjamin Netanyahu said in early November, rejecting calls for a cease-fire in Gaza. "I promise to all citizens of Israel: We will get the job done. We will press ahead until victory."

Over the course of its ground offensive against the Islamist militant Hamas group, which had massacred more than 1,400 people in terror attacks in southern Israel a month ago, the Israeli military has cut the Gaza Strip in two halves and is now encircling Gaza City. House-to-house fighting is still limited to rather rural areas, but soon it is likely to spill over to the bombed out city.  

"This is an operation for which Israeli troops are extremely well prepared," British military analyst Frank Ledwidge, of Portsmouth University, told DW. "They are more experienced in urban fighting than any other armed force in the world."

For years, the Israeli army has been training house-to-house fighting in a special facility in the Negev desert. Now, however, war has become a reality.

Urban combat 'extremely difficult'

The US, which supports Israel militarily as well as diplomatically and acts as an advisor to the Israeli government, cautions against exaggerated expectations. Fighting in an urban environment is "extremely difficult" and "goes at a slow pace," US Defense Secretary Lloyd Austin told broadcaster ABC in October.

The Americans know what they are talking about. Heavy fighting between the US-led coalition and the so-called "Islamic State” group in Syria and Iraq led to casualties among the civilian population. According to some estimates, around 10,000 civilians died in 2016 and 2017 during the battle for Mosul. The house-to-house, street-to-street fighting went on for a full nine months.

Hamas, designated a terrorist organization by the EU, Germany, the US and others, is better equipped militarily and is backed by Iran and the Lebanon-based Islamist Hezbollah militia. US President Joe Biden had already warned Israel during his visit at the end of October not to repeat the US' mistake following the terror attacks on September 11, 2001, and be guided by rage.

Attacks from everywhere

Israel's troops are far greater in numbers than Hamas. Israel mobilized 300,000 reservists after the October 7 attack and Hamas is thought to have around 40,000 fighters. But the Palestinian militants have one huge advantage: They are familiar with the territory and have been preparing for this for a long time.

Ledwidge specified some of the particular challenges that come with urban warfare. Booby traps, he says, are the biggest problem. There are hidden triggers lurking in buildings, many now only ruins following Israeli airstrikes and artillery fire. Removing those traps is a difficult and arduous process.

The complex tunnel system in the Gaza Strip poses a singular problem. Particularly in densely built-up areas, "fighters can move between the buildings without actually going outside into the street," Ledwidge said, meaning that Israeli soldiers can be easily ambushed.

"Urban fighting is a three-dimensional activity," said Ledwidge. "You can be attacked from in front, from behind and from above [with drones]. And in Gaza, also [through tunnels] from below."

In addition, Israeli soldiers are facing the danger of being abducted and taken hostage. They would then have to be added to the more than 200 Israeli civilian hostages who still remain in Hamas' captivity. Hamas is still able to use them as bargaining chips. However, if the Israeli army made a straight attempt at liberating them, Hamas would kill them, many experts believe.

The difficulty of telling terrorists from non-combatants

Finally there's the delicate issue of Palestinian civilians in the Gaza Strip and Hamas' tactics of using them as human shields. The US and other Western governments, including Germany, urgently appealed to Israel to spare civilians. Israel promised to comply, but according to the Hamas-controlled Health Ministry more than 10,000 people have already been killed in Israel's attacks.

Israel has asked civilians in the Gaza Strip to leave the northern part, which is the main combat area in the fight against Hamas. Hundreds of thousands of people, however, are still there. "It is very difficult [in house-to-house fighting] to distinguish between those who are Hamas terrorists and those who are non-combatants," Ledwidge said.

When they caution against civilian casualties during Israel's offensive, Western governments are also bearing in mind that there's the danger of a regional escalation.

"Hamas' aim is to produce horrific images of dead Palestinian civilians and thereby drag Iran and its proxies into the conflict," Hans-Jakob Schindler, of the International NGO Counter Extremism Project, recently told DW.

On Friday, in his first speech since the beginning of the current conflict, Hezbollah leader Hassan Nasrallah did not, however, call for war against Israel.

"It looks as if the chances of regional escalation are now significantly reduced, in the short term anyway," said Ledwidge. "He's been quite realistic and I think taking account of the fact that 70% of the Lebanese people want this war confined to what they call Palestine." 

What lies ahead?

Israel's Defense Minister Yoav Gallant believes that the fight will, in any case, continue for quite some time. "It will take a month, two months, three, but in the end, there will be no Hamas," Gallant said on October 22, speaking at the Israeli Air Force's command center in Tel Aviv.

But even if the Lebanese Hezbollah militia does not open a second front in the north and Israel manages to defeat Hamas, the question of what comes next remains. The most recent major ground offensive carried out by Israel in the Gaza Strip was initiated in July 2014, ten days after massive airstrikes had begun. The armed conflict went on for nearly two months in total.

At the time, however, the aim was not to destroy Hamas completely. And at this point, Israel's plans for the period after the end of its ground offensive in the Gaza Strip remain unclear.

This article was originally written in German.