Prime Minister Benjamin Netanyahu of Israel returned from Washington on Wednesday to a nearly unanimous assessment among Israelis that despite his forceful defense of Israel’s security interests, hopes were dashed that his visit might advance peace negotiations with the Palestinians.

One of the widely articulated goals of his trip, where he met with President Obama and addressed Congress, was to find a way to lure the Palestinians back to direct negotiations, thereby preempting their plan to approach the United Nations in September for recognition of statehood within the pre-1967 lines.

Instead, the Palestinians now say, Mr. Netanyahu’s speeches persuaded them that they had no negotiating partner. They plan to intensify their United Nations efforts, leaving Israelis worried about increasing international isolation and pressure.

A cartoon in the centrist newspaper Yediot Aharonot illustrated the concern. It showed Mr. Netanyahu’s returning plane flying near a volcano. Inside the plane someone says, “All in all, it was a very successful visit.” From the volcano, smoke rises that spells out “S-E-P-T-E-M-B-E-R.”

Newspapers and airwaves were filled with similar commentary. Avi Dichter, a former head of the Shin Bet internal security service and a Parliament member from the centrist Kadima Party, said on Israel Radio, “My fear is that this round of speeches in the United States may leave us and the Palestinians with a closed door.” He added, “It is impossible that in the present reality in the Middle East and here between the sea and the Jordan River we have no next step.”

The praise here for Mr. Netanyahu’s oratory skill on Tuesday in Congress was overwhelming, even from his enemies. Disputes about his performance were limited to how many times he brought the senators and representatives to their feet (from 26 to 34).

Ben Caspit, a columnist for the newspaper Maariv, who spends much of his time attacking the prime minister, wrote, “This was a good speech, brilliantly delivered, with all the tricks and shticks and highlights in the right places.” He said Mr. Netanyahu was “focused, charismatic and self-confident” and called his address to Congress “a sweeping personal victory.”

But Mr. Caspit asked whether it was also a national victory. His reply: “O.K., it depends whom you ask, from what angle you look, and what you’re scared of. Those who are scared of peace yesterday got their wish. Those who are scared of war will be a lot more scared today.”

Mr. Netanyahu’s trip to Washington, at the invitation of the House speaker, John A. Boehner, Republican of Ohio, had been planned before Fatah, the party that dominates the Palestinian Authority, announced a surprise unity accord with Hamas, the Islamist party that rules in Gaza and that has refused to accept Israel’s right to exist.

The original idea was that he might announce a new way forward for Palestinian statehood in the West Bank and Gaza. But once the Palestinian agreement was revealed, Mr. Netanyahu felt less compelled to offer a plan because Hamas is labeled a terrorist group by both Israel and the United States and he believes that its affiliation with any government is dangerous and illegitimate.

The day before Mr. Netanyahu arrived in Washington, he had an additional surprise. President Obama announced that peace should be based on the 1967 borders with mutually agreed swaps. Mr. Netanyahu, who says that formula would render Israel too vulnerable, spent much of his visit shooting down that approach and laying out other elements he considered essential for a lasting peace.

Among those were his contentions that Israel would have to leave certain settlements and would be “generous” in determining the size of the Palestinian state. These angered the right. But he also put forward conditions.

They include a long-term Israeli military presence along the Jordan River to protect Israel’s eastern border from countries like Iran or Iraq; Jerusalem united under Israeli rule; a rejection of any return of Palestinian refugees or their descendants to Israel; a rejection of the deal with Hamas; and Palestinian recognition of Israel as a Jewish state.

Nahum Barnea, a widely read columnist for Yediot Aharonot, who accompanied Mr. Netanyahu to Washington, wrote that while the prime minister spoke well, the visit’s results were worrying. He listed them as “a president whom the Israelis suspect and the Arab world scorns for having yielded to the dictate of the Israelis; negotiations that had a slim chance of being renewed before the visit and now have no chance at all; a Palestinian Authority and an Arab League that are more determined than in the past to reach a resolution in the United Nations General Assembly on a state within the 1967 borders, which is a resolution that has quite dangerous consequences for Israel.”

While Palestinians consider the peace demands by Mr. Netanyahu unacceptable, most are matters of consensus here. The right in Israel comprises those who oppose giving up the West Bank for a Palestinian state because they consider it the land of the Jews, and those who oppose doing so now because they do not trust the Palestinians and fear for Israel’s security.

A poll commissioned by Maariv, and conducted in one day, found that Mr. Netanyahu’s popularity rose slightly after his Washington visit. Asked who was best suited to be prime minister of Israel, he took 37 percent. Second place went to Tzipi Livni, head of the centrist Kadima Party, with 28 percent, followed by Foreign Minister Avigdor Lieberman, head of the ultranationalist Yisrael Beiteinu party, with 9 percent.

As many commentators noted, the question is what happens next in the Palestinian areas.

The Palestinian leadership on Wednesday said it would be consulting with Arab foreign ministers this weekend to decide how to proceed. President Mahmoud Abbas of the Palestinian Authority said negotiations were still his preference but not on the conditions enunciated by Mr. Netanyahu. Israelis are looking ahead with worry.

Itamar Rabinovich, a former ambassador to Washington and president of Tel Aviv University, wrote on the online news site Walla that both Mr. Obama and Mr. Netanyahu were fine speakers who gave good speeches. But, “September and the United Nations General Assembly are around the corner, and without a resumption of negotiations or another substantive step, we face a serious challenge.”

He summed up his concern this way: “What will we do tomorrow morning?”