Ex-SOCOM head warns an Israeli invasion of Gaza will be harder than even the toughest battle against ISIS

• More than two weeks after the Hamas terror attacks, the Israeli ground invasion is yet to begin.
• A ground fight in Gaza would likely feature brutal urban combat, including surprise and guerilla tactics.

Current and former US military leaders are warning that an Israeli invasion of the Gaza Strip, should the military go forward with it, will be more difficult than even the toughest battle against the Islamic State.

More than two weeks after the October 7 Hamas terror attacks, the Israel Defense Forces (IDF) continue to prepare for an expected ground assault into a densely populated coastal enclave to crush the militant group. There, in Gaza, Israeli soldiers could face a prolonged urban combat, brutal fighting which may feature heavy civilian casualties, booby traps, surprise attacks, and guerilla tactics.

The potential Israeli invasion has drawn comparisons to recent examples of intense urban warfare, such as the battles between US-led coalition forces and ISIS in the Syrian city of Raqqa and the Iraqi city of Mosul, the latter of which was described by Western generals as the toughest and deadliest urban combat since World War II.

But amid these comparisons, experts, officials, and former military leaders have warned that Hamas is better armed and more prepared than ISIS was for those fights, and it also has the advantage of its infamous network of tunnels that's so vast it's been referred to by Israel as Gaza's "metro."

"There's a difference between being dug in, going to ground and what we are seeing in Gaza, which is an underground architecture that connects different parts of Gaza and allows people to move supplies, people and other things, and enhance critical functions underground," retired Army Gen. Joseph Votel, the former commander of US Special Operations Command (SOCOM), told the Associated Press in a recent interview.

"I don't think ISIS got to that particular level of sophistication," said Votel, who oversaw military operations against ISIS as commander of US Central Command (CENTCOM) between March 2016 and March 2019.

In contrast with Israel's situation with Gaza, Votel said, the US and its coalition partners had much more time to prepare for the fight in Mosul, which took place from 2016 to 2017. The push to liberate Mosul was bloody and intense and seen at the time as the largest military operation in the last 15 years.

When asked on Sunday by ABC's Jonathan Karl about how the lessons learned in Mosul could apply to Gaza, US Defense Secretary Lloyd Austin said urban combat "is extremely difficult" and moves "at a slow pace." But unlike the fight for Mosul, Austin said Gaza might be a more difficult battle because of Hamas' tunnel network "and the fact that they have had a long time to prepare for a fight."

"One of the things we've learned is how to account for civilians in the battle space, and they are a part of the battle space, and we, in accordance of the law of war, we've got to do what's necessary to protect those civilians," Austin said.

Gaza is home to over 2 million people. Many have been asked by the IDF to evacuate their homes, but many have chosen not to or simply can't, leaving the combat zone filled with civilians. Also complicating the potential invasion is the fact that Hamas is thought to be holding over 200 hostages who were captured during the October 7 attacks against Israel, in which some 1,400 people were killed and another 5,400 left injured. The relentless Israeli bombardment of Gaza, which began immediately after the massacre and is still ongoing ahead of any potential invasion, has killed over 5,700 Palestinians and injured over 16,000 more, according to the Hamas-run Gaza health ministry.

The Biden administration has said that it has been holding conversations with counterparts in Israel about efforts to minimize civilian casualties in trying to pursue Hamas, which Israeli officials have vowed to completely remove from power in Gaza during what they anticipate will be a long fight, but the US still cautioned that it will be a costly affair.

"This is war. It is combat. It is bloody. It is ugly, and it's going to be messy. And innocent civilians are going to be hurt going forward," White House National Security Council Spokesperson John Kirby told reporters at a briefing on Tuesday. "I wish I could tell you something different. I wish that that wasn't going to happen. But it is — it is going to happen."

As questions loom over when — or if — the ground invasion will begin, fears continue to mount that Israel's war with Hamas could escalate into a wider regional conflict that draws in Iran or one of its many proxy groups across the Middle East. In a bid to deter this from happening and signal support to Israel, the US is moving a massive collection of military assets to the region, including aircraft carriers, warships, fighter jets, air-defense systems, and troops. Much of that is already in position, but more is on the way.