Explained | How the Israel-Iran conflict could spiral into more turmoil

Paris: After a fiery night of Israeli attacks across Iran, followed by a fusillade of Iranian missiles launched at Israeli cities in retaliation, the Middle East awoke Saturday to a radically reshaped landscape, with the combatants digging in.

Prime Minister Benjamin Netanyahu vowed that Israel's assault would last "as many days as it takes" to eliminate any nuclear threat Iran could pose against Israel. President Donald Trump piled on, casting the stakes in near-apocalyptic terms for Iran.

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"Iran must make a deal, before there is nothing left, and save what was once known as the Iranian Empire," he posted on social media, hours after Israeli jets struck dozens of targets, killing much of Iran's military high command.

Both men appeared to be gambling. In Netanyahu's case, that Israel's barrage of attacks would fatally damage Iran's nuclear program and decapitate its military leadership. And in Trump's case, that the assault would weaken Iran and force it into a diplomatic accommodation with the United States without spiraling into unintended, potentially catastrophic consequences.

For other world leaders, including Prime Minister Keir Starmer of Britain and President Emmanuel Macron of France, those consequences loomed large. They urged restraint, warning of ripple effects in a region that has been at war on multiple fronts, from the Gaza Strip to the Israeli offensive against Hezbollah in Lebanon and the attacks of the Houthi rebels on shipping in the Persian Gulf.

Israel's audacious attack will almost certainly torpedo Trump's attempts to broker a deal curbing Iran's nuclear ambitions. His implication that the Israeli attack could be a lever to soften up the Iranian leadership for diplomacy seemed far-fetched in the wake of images of burning apartment towers in Iran's capital, Tehran.

Oil prices spiked and stock markets skidded as the prospect of a wider war rattled a world already buffeted by Trump's zigzag course on tariffs. What loomed above all was the uncertainty about what comes next.

Among the many questions after the strikes:

Will Israel be able to cripple Iran's nuclear program, especially Fordo, one of the most critical uranium enrichment facilities, buried deep in the side of a mountain? Israeli fighter jets struck the site early Saturday, Iranian authorities told the International Atomic Energy Agency.

Will the strikes impel Iran to make a dash for a nuclear bomb, presuming it still has the capacity after the attacks on sites and the killing of Iranian scientists? Experts warn that Iran could withdraw from the Nuclear Nonproliferation Treaty, which in turn could set off a regional nuclear arms race. (Israel is not a signatory to the treaty and has never confirmed it possesses nuclear weapons.)

Will the United States be dragged into the conflict beyond what it has done to defend Israel from Iran's retaliation? If it is, will that expose U.S. troops and assets in the region to attacks by Iran or its proxies? The United States has moved diplomatic personnel out of vulnerable locations like Iraq.

Will the United States be able to prevent the conflict from metastasizing into a regionwide war? If it does spiral, how would that affect the calculus of Russia with its war in Ukraine and China with its designs on Taiwan? Both could exploit a United States preoccupied by another quagmire in the Middle East.

"Trump may have calculated that this was a bargaining move," said Vali R. Nasr, a former dean of the Johns Hopkins School of Advanced International Studies. "But it is a big gamble. If the U.S. gets dragged into a war, the entire geopolitical map -- from Paris to Moscow to Washington to Beijing -- will change."

Nasr, who served in the State Department during the Obama administration, said Trump's immediate challenge would be to prevent such an escalation. While Starmer, Macron and other leaders have urged restraint, the U.S. president is the only figure who can play a decisive role.

To do that, Nasr said, Trump will have to put pressure not only on Iran, but on Netanyahu, who has left no doubt that he views these strikes as the opening salvo in a sustained operation to extinguish Iran's nuclear threat.

A regionwide war, Nasr said, would upend Trump's foreign policy agenda, which is tilted toward trade policy and economic competition with China. During the 2024 presidential campaign, Trump presented himself as a peacemaker in Ukraine and the Middle East -- goals that now look more elusive than ever.

"Trump came into office saying the big geopolitical challenge was the rivalry with China," Nasr said. "He's being sucked into a conflict he didn't want on an issue that is third or fourth on his list of priorities."

Oil prices soared more than 10% after news of the attacks broke. A wider war would deal a blow to global growth, generating another source of uncertainty at a time when Trump's erratic course on tariffs has disrupted trade flows between the United States and dozens of trading partners.

Persuading Israel not to strike Iran's nuclear facilities had been an article of faith among U.S. officials dating back more than a decade. Fears of an attack crested during the Obama administration because of Netanyahu's outspoken opposition to the nuclear deal negotiated by President Barack Obama.

But the success of Israel's more targeted strikes against Iran in recent months -- as well as their limited spillover in the region -- quelled the anxiety of U.S. officials that an Israeli attack would have calamitous consequences.

Some analysts warned that Israel's all-out assault could badly tarnish the credibility of the United States. Unlike a few years ago, when Persian Gulf countries tacitly favored an Israeli strike on Iran, viewing it as a strategic enemy, Saudi Arabia and other Persian Gulf states lobbied against Israeli military action this time.

"The U.S. now faces a reality where basically the entire region views its closest ally, Israel, as the primary destabilizing force and driver of radicalization in the region," said Daniel Levy, a former Israeli peace negotiator who now runs the U.S./Middle East Project, a research group in London and New York.

Moreover, he said, the timing of the attack, just days before the next scheduled round of negotiations between Iranian officials and Trump's special envoy, Steve Witkoff, in Oman, raises the risk that other countries will regard U.S. diplomacy as merely a distraction intended to give Israeli warplanes a greater element of surprise. (Iran has said it will not take part in the talks.)

If that hardens into conventional wisdom, Levy said, it could encourage other countries to act preemptively in parts of the world that are not in a state of conflict, but where they fear a similarly disruptive United States.

For Iran, the stakes are no less profound. Israel's waves of aerial attacks, augmented by Israeli intelligence agents operating inside Iran, have exposed, again, the glaring weaknesses in Iran's defenses.

"Iran has a weak hand to play, compared to one year ago," said Karim Sadjadpour, a senior fellow and expert on Iran at the Carnegie Endowment for International Peace, a think tank in Washington.

With Israel having decimated Hamas and Hezbollah, the Iranians would have to rely on Houthi proxies to carry out reprisals against Israel or the United States. And the Houthis themselves have been targeted by the Americans.

Iran's choices are all bad, Sadjadpour said. If it attacks oil installations in Saudi Arabia, it risks U.S. military retaliation. If it announces plans to race for a bomb, it faces retaliation from Israel, as well as from the United States, which has long said it would not allow Iran to develop a nuclear weapons ability.

"Compounding Iran's vulnerabilities," he said, "its key military leaders and strategists who would prepare their retaliation have already been assassinated."