The leader of Hamas, Yahya Sinwar, has become fatalistic after nearly a year of war in Gaza and is determined to see Israel embroiled in a wider regional conflict, U.S. officials said.
Mr. Sinwar has long believed he will not survive the war, a view that has hindered negotiations to secure the release of hostages seized by his group in the Oct. 7 attacks in Israel, according to U.S. intelligence assessments.
His attitude has hardened in recent weeks, U.S. officials say, and American negotiators now believe that Hamas has no intention of reaching a deal with Israel.
Prime Minister Benjamin Netanyahu of Israel has also rejected proposals in the negotiations and added positions that have complicated the talks. U.S. officials assess that he is mainly concerned about his political survival and might not think a cease-fire in Gaza is in his interests.
Hamas has shown no desire at all to engage in talks in recent weeks, U.S. officials say. They suspect that Mr. Sinwar has grown more resigned as Israeli forces pursue him and talk about closing in on him.
A larger war that puts pressure on Israel and its military would, in Mr. Sinwar’s assessment, force them to scale back operations in Gaza, the U.S. officials said.
The war in the region has widened, but not in ways that have meaningfully benefited Hamas, at least not yet.
Immediately after Oct. 7, Hezbollah began carrying out strikes in northern Israel in a show of solidarity with Hamas. While the attacks drove Israelis from their homes, they did not put pressure on the military. Hezbollah’s leaders did not want to start a new war with Israel, U.S. officials assessed at the time.
Since the Israeli campaign against Hezbollah began last month, the group has not launched a major counterattack on Israel, much less opened an offensive front. Israeli and U.S. officials say Israel has destroyed half of the militia’s arsenal and killed many of its leaders.
Israeli troops moved into southern Lebanon this week, after a nearly monthlong bombing and sabotage campaign that included a strike that killed Hassan Nasrallah, the leader of Hezbollah.
Iran, which backs Hezbollah and Hamas, unleashed a missile barrage against Israel on Tuesday in response to the killing of Mr. Nasrallah. But most of the missiles were shot down or failed to do any real damage.
The failure of Hezbollah or Iran to meaningfully damage Israel, at least so far, is a telling sign of Mr. Sinwar’s miscalculation, American officials said.
Isolated and in hiding in Gaza, Mr. Sinwar’s communication with his organization has become strained. He stopped using electronic devices long ago and stays in touch with his organization through a network of human couriers, according to Israeli and American officials.
The pace of Israeli operations in Gaza has slowed, as Israeli leaders have shifted their attention to the north. Israeli forces are now in just a few positions in Gaza, including what they call the Philadelphi Corridor between the enclave and Egypt. While Israel has not launched a major raid into civilian areas of Gaza for weeks, it still conducts daily airstrikes targeting Hamas.
As a result, the toll on civilians in Gaza continues. In a 24-hour stretch on Wednesday and Thursday, the Israeli military killed 99 Palestinians in the enclave, local health officials said, one of the highest death tolls in months.
Talks to broker a cease-fire in Gaza and release the Israeli hostages have broken down. Mr. Netanyahu has added demands and revived some that had previously been dropped, frustrating international negotiators. And Mr. Sinwar has become far more inflexible, U.S. officials say.
His actions and motivations have long been a focus of the American intelligence community. But after Oct. 7, the spy agencies intensified their work on the Hamas leader, forming a targeting cell to study and hunt him.
For months, intelligence agencies have assessed that Mr. Sinwar has a fatalistic attitude and cares more about inflicting pain on Israelis than helping Palestinians. U.S. officials will not discuss their recent intelligence collection on him, but the view that his attitude is hardening comes from officials studying his negotiating stances and classified reports.
Mr. Sinwar’s position stiffened this summer after Israel assassinated Ismail Haniyeh, the political leader of Hamas based in Qatar and one of the chief negotiators. Mr. Haniyeh was a more conciliatory negotiator who was interested in making a deal, and U.S. officials say he was willing to push back against Mr. Sinwar’s more extreme demands. Israel’s decision to kill a top Hamas leader who was negotiating a cease-fire infuriated the group and Mr. Sinwar, according to U.S. officials.
Some Israeli officials have questioned whether Mr. Sinwar is still alive. U.S. and Israeli officials acknowledge there is no definitive proof of life. There have been no audio or video recordings from him for months.
On Sept. 13, Hezbollah released a letter that Mr. Sinwar sent in support of Mr. Nasrallah. Some Hamas officials, speaking elliptically, suggested that it was written outside Gaza by someone else, with Mr. Sinwar’s approval. It was not handwritten, unlike other communications that have been verified to come directly from him.
But American officials said they had no evidence he was dead, and in fact senior U.S. officials said they thought he was alive and making critical decisions for Hamas.
Mr. Sinwar remains in hiding but appears to recognize that Israeli forces are closing in on him. They came near his position in August, with Defense Minister Yoav Gallant of Israel saying that their forces had discovered signs that the Hamas leader had spent time in the warren of tunnels beneath Rafah, in southern Gaza.
“When we entered the tunnels under Rafah, where the hostages were murdered, we found signs of Sinwar’s past presence in Tel Sultan,” Mr. Gallant told reporters recently, referring to six hostages who were believed to have been killed in a neighborhood of Gaza, near Rafah.
While Mr. Sinwar’s strategy is not yet working, it could ultimately succeed.
Israeli forces are fighting Hezbollah on its home territory in southern Lebanon. While the Israeli government is promising a limited incursion in Lebanon, so far the military operations have been large-scale.
The fighting has already proved difficult: At least nine soldiers were killed in the first days of close-quarter combat. If the intense fighting continues, and Iran is drawn in, Mr. Sinwar could get his wish of a multifront war that eases pressure on Hamas.
Iran and Israel could continue to trade ballistic missile strikes. If one weapon causes immense damage, a larger conflict might erupt.
American officials are waiting to see whether the conflict between Iran and Israel escalates further. They do not believe that Iran wants a full-scale war with Israel or to directly intervene to help Hamas. But they also publicly support a planned Israeli strike against Iran in retaliation for the ballistic missile attack this week.
“Iran will hold a grudge for Nasrallah’s killing,” said Scott D. Berrier, a retired lieutenant general and the former head of the U.S. Defense Intelligence Agency. “But their options are limited. I don’t see Iran going toe to toe with Israel anytime soon.”
A senior U.S. official said Iran’s actions over the past few months had sent a clear message to Mr. Sinwar: “The cavalry is not coming.”
Julian E. Barnes and Adam Goldman reported from Washington, and Edward Wong reported from New York and Washington. Adam Rasgon and Aaron Boxerman contributed reporting from Jerusalem, and Ronen Bergman from Tel Aviv.
