As Prime Minister Benjamin Netanyahu returned from a visit to Washington this week, much of the discussion here centered on traffic-light hues. Had the Israeli leader been given a red light or a green light about attacking Iran’s nuclear facilities?

The general assessment was that President Obama’s signal — his appeals to give diplomacy more time and his pledges of support for Israel — fell somewhere on the spectrum between yellow and red. To many here, that probably came as a relief.

Amid an escalating din among Israeli leaders about the threat of a potentially nuclear Iran, the Israeli public has displayed little enthusiasm for a solo preemptive military strike. A handful of recent polls have shown that ordinary Israelis are firmly against the idea of going it alone.

“Israelis are much more careful, much more cautious than their government,” said Ephraim Yaar, a Tel Aviv University professor who co-directs a monthly public opinion survey. This week, more than 60 percent of Israelis polled said they opposed an attack on Iran without U.S. cooperation.

In the will-they-or-won’t-they guessing game that discussion about a military strike has become here, few view public opinion as a predictor of outcome. Netanyahu is sharply attuned to public sentiment, analysts say, but he has repeatedly emphasized — most recently in Washington — that he is driven by an obligation to protect Israel even without U.S. blessing, though he clearly wants it.

So, too, do Israelis, though that is not out of deference to the United States, said Yaar, whose survey was conducted just before Netanyahu’s trip. Commentators and retired security officials have questioned whether the Israeli military has the capacity to carry off a solo assault. The Israeli public shares that doubt, the survey found — and believes that Iranian retaliation could kill more than 500 civilians, the figure estimated by Israeli Defense Minister Ehud Barak in November.

In a column published Thursday in the Hebrew-language newspaper Maariv, columnist Yael Paz-Melamed echoed some of those concerns, accusing Netanyahu of making a more forceful case for action against Iran in Washington than he had at home. A strike could engulf the nation in a bloody conflict, she argued, and it is unclear whether a nuclear-armed Iran really would be more dangerous than a war with Iran.

“Had Netanyahu delivered his speech to 14,000 Israelis, he would have had to address those questions. Because this is about our lives and our fate,” Melamed wrote, referring to the reported attendance at a conference sponsored by the American Israel Public Affairs Committee, a pro-Israel lobbying group, that the prime minister addressed Monday in Washington.

Though Netanyahu won no concrete public promises of U.S. military action, his visit to Washington was broadly depicted here as successful. Iran’s nuclear ambitions shot to the forefront of the American policy agenda, and Obama made clear that the United States also judged them to be a global security threat, said Eytan Gilboa, a professor of communications and political science at Israel’s Bar-Ilan University.

“I happen to believe much of the talk here about military action was designed to affect the policies of the United States and Europe. But people are worried here,” Gilboa said in an interview. “When the United States says time and again that it would not allow Iran to become a nuclear power and it would use all means, including military force, if nothing works, that reassures people.”

Not everyone, of course. Moshe Levin, a retired graphic designer buying a sandwich at a downtown Jerusalem shop this week, said Netanyahu had seemed like a “beggar” seeking U.S. protection. Obama spoke eloquently, Levin said, but his cautious approach simply underscored how differently Americans, thousands of miles away, perceive the threat of an Iranian bomb.

“Obama didn’t give me anything to depend on,” the 70-year-old said. “Nobody believes that the sanctions [against Iran] now are effective.”

Israeli officials maintain that a military strike remains under consideration, despite Washington’s pleas for patience. Though Obama did not give approval for such a strike, “there wasn’t an unequivocal prohibition either,” the head of the prime minister’s National Information Directorate, Liran Dan, told Israel’s Army Radio on Wednesday.

Netanyahu returned to Israel on the eve of Purim, a holiday celebrating the biblical story of the Jews’ escape from a massacre plotted by Haman, a king’s minister in ancient Persia. Now, Netanyahu said, Jews “have a strong state and army. . . . We can defend ourselves.”

On Wednesday afternoon, parents in central Jerusalem held the hands of children costumed as fairies and superheroes, in commemoration of the holiday. Yael Nahari, a museum guide waiting for a tram, said the connection between the Purim story and the modern-day debate had not occurred to her. But she said she hoped the present scenario would end less dramatically.

“We must first try the diplomatic possibilities,” said Nahari, 34. An Israeli strike, she said, should happen only “if there are really no other options.”