Rocket fire from Gaza has markedly declined. The Lebanese border is quiet. Terrorist attacks from the West Bank are rare. The national airport processed a record number of travelers in the first week of August. The currency is so strong that the central bank has bought billions of dollars to keep the exchange rate down.

Israel is flourishing this summer, and one might imagine its people and leaders to be breathing a sigh of relief after nearly a decade of violence and unease. That, however, is far from the case. On every front, Israel is worried that it is living a false calm that could explode at any moment. Its airwaves and public discourse are filled with menace and concern.

“This is a deceptive quiet,” said Daniel Ayalon, the deputy foreign minister. “When a sunny day turns cloudy, it can happen very quickly.”

This week, Prime Minister Benjamin Netanyahu warned that if, as expected, Hezbollah joined the government being formed in Lebanon, any attack on Israel from Lebanon would be seen as the responsibility of the Beirut government. “It cannot hide and say, ‘It’s Hezbollah, we don’t control them,’ ” he said.

Dan Meridor, the minister of intelligence, told Israel Radio that Hezbollah “is purchasing and installing — with Iranian influence and assistance — ballistic systems and other systems of all kinds.”

Those warnings followed a mid-July explosion of a Hezbollah arms cache in southern Lebanon that Israel said pointed to the group’s continuing military buildup, now reaching 40,000 rockets, in violation of United Nations resolutions. Three years ago, Israel and Hezbollah fought a monthlong war after the Lebanese group staged a cross-border raid aimed at killing and kidnapping Israeli soldiers.

Israeli officials say there are credible reports that Hezbollah tried to kill the Israeli ambassador in Cairo recently and was planning attacks on Israeli tourists overseas — although they have declined to elaborate on the nature of the reports to journalists or even to their own diplomats. They have, however, issued harsh warnings.

Hezbollah, like Hamas in Gaza, is a client of Israel’s overwhelming strategic concern, Iran. Israel believes that Iran is hurtling toward nuclear weapons capacity amid a campaign to delegitimize Israel. If Iran develops nuclear arms, officials here say, the result will be a dangerous regional arms race and a sense of immunity for Hamas and Hezbollah.

The Obama administration also believes that Iran has nuclear ambitions, but hopes to curb them through diplomacy or sanctions. The Israelis, dismissive of the diplomacy and skeptical of the prospects for the success of sanctions, have focused on how Iran’s program can be halted militarily.

In recent years, Israel has used its military to end the violent Palestinian uprising, stop rocket fire from Hezbollah and Hamas, and destroy what American and Israeli officials believe to be a Syrian nuclear site. The actions were severely criticized as being inappropriate and ineffective, but most Israelis now believe they were successful, while regarding diplomacy as far less effective.

American officials have discouraged Israel from thinking along such lines, saying that diplomacy with Iran must be given a chance. Israeli officials are worried that the window to stop Iran will close over the next year as it enriches more uranium and acquires the means to stop an attack. At the same time, carrying out an attack without American approval could damage Israel’s vital relationship with Washington.

Tensions with Washington are already higher than they had been in two decades because of an American demand that Israel stop building settlements in the West Bank and East Jerusalem. Israel says this places undue emphasis on something that is less central to Middle East peace than many abroad assert. It remains unclear how this dispute can end happily for all sides, especially the Palestinians, who consider an end to settlement construction vital to any future peace deal.

Meanwhile, the debates inside the Fatah movement’s congress in Bethlehem over the past week — partly about resistance to occupation and the possibility of reviving military struggle — stirred concerns in Israel. It was a balancing act for a movement that backs negotiations but keeps an eye on its street. Many Israelis tended to see the debate as further evidence that an agreement was not imminent.

Foreign Minister Avigdor Lieberman said, for example, that the positions taken by Fatah put off by some years any possibility of a peace deal.

Israel’s critics and opponents argue that its problems are mostly self-imposed, the result of paranoid aggression and a failure to grasp the impact of its own words and actions. The concern on the streets in Beirut this summer, for example, is that Israel is planning another war there, and that is the reason for the frequent warnings aimed at Lebanon.

Most Palestinians say they believe that Israel wants tight security and slightly increased prosperity in the West Bank as a substitute for real progress toward an independent Palestinian state. They complain that when Israel feels threatened it refuses to negotiate, yet when it feels calm it sees no need to.

Israel continues a tight embargo on goods entering Gaza, partly as pressure to get back a kidnapped soldier held there for three years and partly to increase the gap in living standards with the West Bank. The idea is that once the Fatah-run West Bank is secure and better off and Gaza remains stagnated and mired in poverty, Palestinians in both places will support Fatah and its negotiated approach.

And while some Fatah leaders are not unhappy with this policy, West Bank leaders are wary of cooperating — or being seen to cooperate.

“We don’t want to make it seem like we are helping to make the occupation work better,” said Salam Fayyad, the Palestinian prime minister, in an interview. “We want an end to Israeli incursions in our cities as well.”

Critics on the left in Israel say they fear that the current calm is leading Israelis away from focusing on how to solve their conflict with the Palestinians.

Aluf Benn, a senior journalist for the leftist newspaper Haaretz, expressed his concern last weekend in an article, saying that the country had lost interest in coming to terms with its neighbors, a process that entails painful sacrifices in the name of coexistence.

“The most important ramification of the present quiet is the fact that it reinforces Israelis’ indifference toward any kind of peace process,” he wrote. “Israelis want peace and quiet. And that’s what they have — and without negotiations or peace accords.”