The Middle East faces its biggest crisis in years as it braces for a potential full-blown war between Iran and Israel that could drag in the entire region.
Israel's suspected killing of Ismail Haniyeh, the political leader of the EU- and U.S.-designated Palestinian terrorist group Hamas, in Tehran on July 31 has pushed the region to the brink.
A major military response by Iran against Israel, which Tehran has promised, could spark an all-out war that would pit Iran and its regional proxies against Israel and the United States, experts say.
"I think this is the first time we're really heading toward a potential full-scale regional confrontation," said Raz Zimmt, a senior researcher at the Israeli-based Institute for National Security Studies.
'Only A Matter Of Time'
The region has been bracing for an Iranian response since the assassination of Haniyeh, who was killed in an affluent neighborhood of Tehran hours after attending the inauguration of President Masud Pezeshkian.
Iran has directly blamed Israel, which has not claimed responsibility for the killing. Iranian Supreme Leader Ayatollah Ali Khamenei has vowed, and reportedly approved, a military response.
Haniyeh's killing came just hours after Israel killed a top commander of Hizballah, the Iran-backed Lebanese extremist group, in Beirut. A member of Iran's Islamic Revolutionary Guards Corps was also killed in the July 30 Israeli air strike.
In April, Iran and Israel appeared to be on the verge of war after Tehran launched an unprecedented direct air attack against its archfoe.
Days later, suspected Israeli strikes hit a military base outside Iran's central city of Isfahan.
Iran launched an unprecedented drone and missile attack against Israel on April 13, but the attack was mostly repelled by Israel's allies, including the United States.
Iran's attack was in retaliation for a suspected Israeli air strike on the Iranian Embassy's compound in Damascus on April 1 that killed seven Iranian commanders.
Tehran's barrage against Israel was highly telegraphed and aimed at deterring future Israeli attacks, experts said. But its response to the killing of Haniyeh on Iranian soil could provoke a harsher response.
"It's much more likely that we will see a combined, orchestrated attack against Israel" from Iran and the so-called axis of resistance, Tehran's loose network of militant groups and proxies that aid it in opposing Israel and the United States, said Zimmt.
"This makes the situation much more complicated because the consequences of an Iranian and Hizballah attack would probably be worse than what happened in April," he added. "That certainly brings us closer to the possibility of a regional campaign."
SEE ALSO: Iran Versus Israel: Who Has The Military Edge?Hizballah and Iran-backed militant groups in Iraq, Syria, and Yemen have carried out attacks against Israel after it launched its devastating war in Gaza, which came shortly after Hamas's October 7 attack in Israel that killed around 1,200 people.
Even as Iran's hostilities with Israel decreased after April, it was "only a matter of time before the next phase of direct confrontation" between the archfoes, said Hamidreza Azizi, a fellow at the German Institute for International and Security Affairs.
"This might be the most dangerous moment in the region in the past few years," he added.
Hard To Rein In
There has been a flurry of diplomacy in the region aimed at easing the escalating tensions between Iran and Israel.
Jordan's foreign minister made a rare visit to Tehran on August 4, during which he pleaded for peace.
Iran has insisted that it is not looking to escalate tensions but that it has a "legitimate right" to hit Israel.
"As far as the violation of our territorial integrity is concerned, we will not make any compromises," Iranian Foreign Ministry spokesman Nasser Kanani said on August 5.
A direct Iran-Israel war would likely drag in the entire region, including Tehran's proxy allies, including Hizballah in Lebanon, the Huthi rebels in Yemen, Hamas in the Palestinian territories, and pro-Iranian militias in Iraq.
Any conflict would also likely draw in the United States, Israel's key ally, which has sent additional warships and fighter jets to the region.
On August 5, a U.S. spokesperson confirmed that "several" American personnel were injured in a rocket attack claimed by pro-Iran fighters on a military base in Iraq.
Ali Vaez, the director of Iran Project at the International Crisis Group, said that signals from Tehran suggest that "they are intent on a larger response" with more drastic consequences.
If Iran's potential attack causes significant damage and casualties, "containing the escalatory cycle becomes far more difficult," Vaez warned.
"This is without doubt the closest we've been to" a direct face-off between Iran, Israel, and their allies, he said.