To pull off the most ambitious and sophisticated attack in the long history of antagonism between the Middle East’s preeminent powers, covert Israeli agents set up a drone base deep inside Iranian territory. They recruited disaffected Iranians to aid their cause. They smuggled weapons systems across enemy lines.These are among the espionage tactics that allowed Israel to conduct its surprise attack on Iran last night, simultaneously eroding Tehran’s defenses and limiting its capacity to retaliate as Israeli forces picked off senior commanders and struck sensitive nuclear sites.The operation, termed “Rising Lion,” signals a new phase in Israel’s efforts to transform extensive intelligence gathering into decisive military campaigns intended to outmaneuver its enemies throughout the Middle East. In recent years, Israel has used intelligence to assassinate top Iranian military officers and nuclear scientists, as well as the leaders of Iran-backed militias. Israel has also targeted sensitive locations within Iran for air strikes.The attacks begun this week, however, were more audacious both in the scope of the targeting and in the clear aim of arresting Tehran’s nuclear ambitions. Among the sites struck was the Natanz Nuclear Facility, where Iran has generated most of its nuclear fuel. Fordow, a facility buried under a mountain, presents a more difficult target. A former U.S. intelligence official with expertise in the Middle East told me that Israel may need U.S. bunker-buster weapons to do more lasting damage to additional Iranian facilities. That makes Washington’s potential support for what is expected to be a drawn-out campaign all the more important.Israeli and other Western officials said the campaign was in its initial stages, and Tehran has vowed a vigorous response, which began after sunset today when it fired dozens of missiles toward Israel—including some that made it through the Iron Dome defensive shield. But current and former U.S. and Israeli officials and analysts told me that the blow already dealt to Iran in the early hours of the attack makes manifest Israel’s advantages.[Read: The war Israel was ready to fight]Iran’s “Axis of Resistance”—a network of militias expected to join in any war with Israel—is flat on its back, degraded by a series of U.S.-enabled Israeli offensives over the last year and a half. Israel weakened Iran’s air-defense systems and missile-production facilities in a pair of strikes conducted last April and October, while also revealing the limits of Iran’s offensive capabilities by fending off drones and missiles in a coordinated effort with Western partners.As a former CIA station chief in Israel told me, the Mossad has “a good network inside Iran, and they have the support of the U.S.” Iran, meanwhile, has shown that it possesses neither strategic foresight nor the technical ability to fend off Israeli operations, the former station chief said, pointing to the 2020 assassinations of Qasem Soleimani, the senior security and intelligence commander, and Mohsen Fakhrizadeh, the top nuclear scientist. “To add to it,” the former senior intelligence officer said, “Iran has few friends, so it’s hard for them to get supplies in.”Iran also has enemies within: A former Israeli intelligence official noted that Iranians opposed to the regime make for a ready recruiting pool, and indicated that Iranians working for Israel were involved in efforts to build a drone base inside the country.Israel’s operation drew on years of intelligence gathering against senior Iranian commanders and scientists and relied on extensive cooperation between the Mossad and the Israeli military. It showed not just technical prowess, homing in on key targets, but also creativity in executing covert action that has been a hallmark of Israel’s multipronged campaign against its enemies in the region. The Mossad released video on Friday of Israeli operatives deploying precision strikes on air-defense systems from inside Iran. Security officials briefed Israeli media on other aspects of the secretive operation, including the use of vehicles to smuggle weapons systems into the country.In a statement late Thursday, in the early hours of the strikes, Secretary of State Marco Rubio said the United States was not involved in the attack. But a former Israeli security official told me there was “no doubt” that Israel had U.S. backing for its actions, even if Trump and his advisers had worked to avert a strike. The former official said the apparent inability of the Iranians to mount a vigorous self-defense made clear that there is “less Iranian capacity than they wanted us all to believe.” Still, the former official said, Tehran will retaliate and “can do much damage over time.”The central questions now are what role Trump intends to play, how severely Iran’s nuclear program is stalled, and whether negotiations can be resumed. “The Israelis are very tactically successful,” Ray Takeyh, a senior fellow for Middle East studies at the Council on Foreign Relations, told me. “But they often confuse short-term success with long-term gain.”[Read: What Trump knew about the attack against Iran]A primary reason the Israelis were determined to act now, Takeyh said, is that they knew they had a limited window for success and needed to strike when Iran had diminished retaliatory capacity through its proxies—among them Hamas in Gaza and Hezbollah in Lebanon. Hamas has been seriously diminished by nearly two years of fighting triggered by its October 7, 2023, assault on Israel. And Hezbollah has been depleted by an extensive conflict with Israel, whose intelligence services succeeded in penetrating the group so extensively that they were able to remotely detonate the militia’s pagers and walkie-talkies last year, killing or maiming scores of fighters.Proxies still in a position to respond militarily, analysts said, include the Houthis in Yemen and Shiite militias in Iraq. The Houthis are perhaps the strongest component of the Iranian-backed axis. The Islamist faction active in northwestern Yemen has continued launching drones and missiles at Israel even as Washington secured a cease-fire agreement with the group, whose attacks on ships in the Red Sea had snarled international trade.U.S. officials told me that Israel feared Iran’s rapid efforts to improve its retaliatory capacities, which added to their feeling that they had a limited window to act. But the inclination for a military solution also reflects a longheld impulse of Israeli Prime Minister Benjamin Netanyahu. Before his second inauguration, in 2009, Netanyahu told Jeffrey Goldberg, now The Atlantic’s editor in chief, that he would have to act if then–President Barack Obama failed to stop Iran’s nuclear program. Obama reached a deal with Iran over Netanyahu’s objections in 2015—a deal that Trump tore up three years later. In the midst of Trump’s attempts to secure a new agreement, Netanyahu has taken his long-promised action.“Since the dawn of the nuclear age, we have not had a fanatic regime that might put its zealotry above its self-interest,” the prime minister said in 2009. “People say that they’ll behave like any other nuclear power. Can you take the risk?”Shane Harris contributed reporting.