One hundred days into his first term as Iran’s president, Hassan Rouhani offered an upbeat progress report to the country Tuesday, two days after a nuclear deal with world powers gave his young administration a much-needed boost. “We pride ourselves on being accountable to our people,” Rouhani said at the start of a live television question-and-answer session in which he outlined his administration’s handling of Iran’s domestic and foreign affairs since taking power in August.

In the aftermath of the interim deal between the Iranian regime and the P5 + 1, the dissonance between the smiles on the faces of Iranian and Western negotiators and the frowns of concern of Prime Minister Binyamin Netanyahu and senior Israeli cabinet ministers reflect the magnitude of Israel’s challenge over the next six months.

The Geneva Agreement is a setback for Israeli diplomacy and a personal defeat for Israeli Prime Minister Benjamin Netanyahu. As the United States and its other allies have sought to respond to what they see as signs of change in Tehran, Mr Netanyahu has stuck grimly to the same message. That is that those signs may be cosmetic and that the world powers are relaxing sanctions without getting much in return.

Going about their business on Monday, Israelis seemed more accepting than their leader, Benjamin Netanyahu, of a nuclear deal with Iran that he rejected as a historic mistake. On the streets of Israeli cities, people questioned about Sunday’s interim accord between global powers and the Islamic Republic voiced doubts about an agreement that Netanyahu said would leave arch-foe Iran within reach of an atomic bomb.

The potentially landmark agreement struck between Iran and world powers over Tehran's nuclear program, after five days of talks in Geneva, was first officially announced on Twitter. It was Michael Mann, the spokesman for EU foreign policy chief Catherine Ashton, who broke news of the deal on Twitter while quoting his boss.

In a victory for diplomacy, world leaders announced early Sunday that a deal had been struck with Iran over its disputed nuclear program. In what U.S. President Barack Obama called an "important first step" toward addressing the world's concerns over Iran’s motivations and actions and opening a path out of a three-decade long standoff, the deal will curb Tehran’s nuclear ambitions away from a bomb and toward a civilian capability, in exchange for limited relief—for now—from strict sanctions that have devastated the Iranian economy.

What's the best evidence that things are really changing in the Mideast? It is the spectacle of Israel and Saudi Arabia, hitherto America's two closest allies in the region, glowering darkly on the sidelines (and more or less in unison) as the United States and Iran begin an engagement that is already more profound than anything we've seen since the Iranian revolution of 1979. This historic shift, punctuated by the signing Saturday of a six-month, nuclear-freeze deal that both Israel and Saudi Arabia had loudly opposed, could potentially transform the entire region.

Secretary of State John Kerry offered a robust defense of the interim nuclear agreement with Iran on Sunday, rejecting comparisons to North Korea and insisting that the deal would make Israel and Persian Gulf allies of the United States more secure, not less so. Speaking on three Sunday news programs, Mr. Kerry said the deal, signed early Sunday morning in Geneva, would lock in place nuclear activities that bring Iran closer to having a bomb and subject its nuclear facilities to unprecedented international inspections.