Hours after Israel launched a massive bombing campaign across Gaza on Tuesday, Hamas’s military wing had not mounted a discernible counterattack.
It was by far the deadliest day since a cease-fire in Gaza began about two months ago. The Gaza health ministry, which doesn’t distinguish between civilians and combatants, said that more than 400 people had been killed in the aerial bombardment that started before dawn.
But throughout the day, there was a notable absence of rocket fire by Palestinian militants or attempts to ambush Israeli soldiers.
Suhail al-Hindi, a Hamas official, reacted to the assault by saying the group hopes to restore the cease-fire but reserves the right to respond.
“How to respond is left to those on the ground,” he said in a telephone interview. “They know and understand how to respond to the occupation.”
There is no question that Israel’s 15-month war against Hamas weakened the group that has long ruled Gaza. Israel killed thousands of its fighters and destroyed much of its tunnel network which was used, among other things, to store weaponry. And it undermined Hamas’s ability to fire rockets at Israel.
Mr. al-Hindi acknowledged that the capabilities of Palestinian militant groups in Gaza were degraded by the war, but he said they still had both the ability and the desire to fight.
“The issue isn’t one of equipment and weapons,” he said. “It’s about will, and I believe there’s lots of will to resist this occupation.”
Hamas has worked to regroup over the last two months since a cease-fire agreement with Israel came into effect. It has been collecting unexploded bombs throughout Gaza and repurposing them as improvised explosive devices, according to one member of the Qassam Brigades, Hamas’s military wing. It has also been recruiting new members and replacing commanders who were killed, the member said, speaking on condition of anonymity to discuss sensitive details.
Seven members of the Israeli parliament’s foreign affairs and defense committee said in a letter that they recently learned that Hamas and Palestinian Islamic Jihad, another militant group in Gaza, have more than 25,000 and 5,000 fighters, respectively, still in the territory.
“The Qassam Brigades is still able to confront the Israeli occupation,” said Ibrahim Madhoun, a Palestinian analyst from Gaza who is close to Hamas.
The lack of any military response to the new Israeli onslaught could mean the group was focused on preparing for a fight in case of an Israeli ground invasion, he said.
The Israeli military has said it was attacking Hamas and Palestinian Islamic Jihad, a smaller militant group in Gaza, targeting groups of fighters, missile launch posts and weapons stockpiles.
The Israeli bombardment followed weeks of unsuccessful negotiations to extend the cease-fire between Israel and Hamas.
Despite the intensity of Israel’s attacks, Mr. Madhoun said Hamas wouldn’t relent to Israeli demands to end its role in Gaza or hand over large numbers of the remaining hostages without guarantees of a permanent end to the war.
“Hamas doesn’t want an escalation, but it will not surrender,” he said.
Israel has been trying to pressure Hamas to release living hostages in exchange for an extension of the cease-fire, without giving the group the reassurances it seeks that the war will end permanently.
Israel has vowed throughout the war that it will not allow Hamas to continue to govern Gaza and will ensure that it can never again mount another attack like the one on Oct. 7, 2023, that set off the war. Prime Minister Benjamin Netanyahu has said that for the war to end, Hamas’s government and military wing must be dismantled, a position shared by his right-wing coalition partners in the government.
While Hamas has suggested it was willing to give up civilian governance of Gaza, it has firmly rejected dissolving its military wing, a critical source of its power in the enclave.
During the initial phase of the cease-fire, the group tried to use handovers of hostages to show it was still a powerful forces in Gaza. Nearly every time it transferred Israeli captives to the Red Cross, it put on theatrical ceremonies featuring hundreds of mask-wearing and gun-toting militants.
Michael Milstein, a former Israeli military intelligence officer specializing in Palestinian affairs, said Hamas may be trying to first gauge whether Israel was planning a long-term assault or a limited salvo before it responds.
“They want to know where things are going,” Mr. Milstein said. “If everything is going to end in two hours, they don’t want to waste what remains of their ammunition. But if it goes on for a long time, they will respond.”
Iyad Abuheweila and Aaron Boxerman contributed reporting to this article.