The Americans say Israel’s forceful response to the attack by Hamas on Oct. 7, in which more than 1,400 people were killed and more than 200 were taken hostage, reflects the importance that it places on re-establishing deterrence against attacks from adversaries in the region. The Israeli military’s aura of power was shaken by the Oct. 7 attack, the officials say.
The unfolding humanitarian crisis in Gaza, where the Hamas-run health ministry says more than 9,400 people have been killed, has provoked outrage in the region, in the United States and around the world, leading the Biden administration to be more vocal in saying that Israel has to do more to protect civilians.
Mr. Blinken urged Israel to agree to a series of pauses in the fighting to facilitate the flow of humanitarian aid into Gaza and the exit of foreign nationals from the enclave, but Mr. Netanyahu rebuffed the idea, saying any pauses would be contingent on the release of all Israeli hostages.
In the first two weeks of the war, roughly 90 percent of the munitions Israel dropped in Gaza were satellite-guided bombs of 1,000 to 2,000 pounds, according to a senior U.S. military official. The rest were 250-pound small-diameter bombs.
Asked about the U.S. request to use smaller bombs, a spokesman for the Israeli Defense Forces, Maj. Nir Dinar, said: “We don’t comment on munitions and our conversations with allies.”
Israel used at least two 2,000-pound bombs during an airstrike on Tuesday on Jabaliya, a dense area just north of Gaza City, according to experts and an analysis conducted by The New York Times of satellite images, photos and videos.
American military officials say that the smaller bombs are much better suited to the dense urban environments of Gaza. But Israel has over the years built up stocks of larger bombs, originally intended to target hardened Hezbollah military positions in Lebanon.
The United States is now trying to send more of the smaller bombs to Israel, said the senior military official. If the United States can get those smaller munitions to Israel, American officials hope they can help Israel mitigate the risk to civilians.
The United States has also increased the amount of intelligence that it is collecting in Gaza: American drones are flying over the enclave, searching for hostages held by Hamas and other groups, and U.S. military satellites have been redirected to monitor the enclave. The United States is also using aircraft on the two carriers in the Mediterranean to help collect additional intelligence, including electronic intercepts.
While the United States has increased the amount of intelligence that it is sharing with Israel, U.S. officials stressed they are not helping Israel pick targets for strikes.
American officials believe the less judicious Israel is, and the greater the Palestinian death toll, the more quickly pressure will build on its leaders to end the military operation. A more targeted campaign, U.S. officials tell them, could go on for longer and do more sustained damage to Hamas’s military wing.
“We do our best to destroy Hamas only, without harming the civilians,” said Iddo Ben-Anat, a deputy brigade commander leading part of the Israeli invasion of Gaza.
Arab leaders met with Mr. Blinken in Amman, Jordan, on Saturday, and demanded an immediate cease-fire, increasing pressure on the Biden administration to do more to rein in the Israeli campaign.
But Mr. Blinken publicly rebuffed the idea, saying, “It’s our view that a cease-fire now would simply leave Hamas in place, and able to regroup and repeat what it did on October 7.”
Democratic lawmakers and terrorism experts have said the higher the civilian casualty toll, the greater the resentment that will build in Gaza, resentment that Hamas can use to build further support.
Representative Seth Moulton, Democrat of Massachusetts and an Iraq war veteran, said the America’s biggest mistake in that conflict was trying to provide “military solutions to fundamentally political problems.”
“Israel is not going to win their war against Hamas, which they have every right to fight, by military means alone,” Mr. Moulton said. “And often the wrong military means, like bombs that kill too many civilians, make the political endgame harder to reach.”
At the news conference in Tel Aviv, Mr. Blinken appeared to obliquely acknowledge that risk, arguing that while Hamas needed to be defeated “physically,” the international community needed to ensure that Hamas does not gain more followers in the process.
Mr. Blinken said that Hamas must be fought not just with military might, but also with “a better future, with a better vision” for the Palestinian people.
“Because in the absence of that, even after Hamas, those who sing the siren song of nihilism will find open ears,” Mr. Blinken said.