After the deadly Hamas-led attacks in Israel on Oct. 7, 2023, and Israel’s devastating invasion of Gaza, many of those groups carried out their own strikes against Israel. But in the year and a half since, Israel launched audacious attacks on those militias in Lebanon, Syria, Yemen and Iran, and the response from the axis has grown increasingly muted.

Hamas, which long governed in Gaza, has been degraded by more than a year of war set off by the October 2023 attack on Israel.

In Lebanon, Hezbollah is battered after its 14-month war with Israel that wiped out the group’s top brass, destroyed much of its arsenal and left the country with a multibillion-dollar bill for reconstruction.

Since a cease-fire agreement in November, Hezbollah has largely not responded to the near-daily Israeli airstrikes in Lebanon that have continued despite the truce — a notable sign of Israel’s degradation of the group, analysts say.

Its stinging defeat also spurred political momentum against the group, undoing its once iron grip on Lebanon’s politics. Hezbollah is now facing growing pressure to disarm, after many Lebanese blamed the group for dragging Lebanon into one of its most destructive wars.

“Beyond military limitations, Hezbollah’s political standing is also strained,” said Johnny Mounayar, a political analyst based in Beirut. “Domestically in Lebanon, opposition to Hezbollah has grown and even former allies are no longer aligned with it.”

Both Hezbollah and Iran also lost a key ally in December, after Syrian rebels — who Hezbollah fought — toppled the Assad government, ousting a key ally of Iran in the region and cutting off the main land route it used to supply weapons and cash to Hezbollah in Lebanon.

Syria’s new authorities have made clear that the Iranian government is not welcome in Syria and have shown an initial willingness to engage with Israel.

Among Iran’s proxies, still intact are Iranian-backed Iraqi militias and the Houthis, though both are more peripheral to the conflict with Israel. Among the handful of major Iraqi militias, a leader of only one that operates primarily in Syria and has attacked Israel — Kata’ib Sayyid al-Shuhada — suggested an armed response to the Israeli attack.

“If the war breaks out then hundreds of suicide bombers will be on time,” the militia’s general secretary, Abu Alaa al-Walae, said in a social media post on Thursday night.

The strongest arm of the axis now appears to be the Houthis in northwestern Yemen, who have been launching rockets and drones at Israel and targeting ships in the Red Sea since October 2023, in what Houthi officials have characterized as a campaign of solidarity with Palestinians in Gaza.

Those attacks appeared to ramp up last month when a Houthi missile landed near a terminal of Israel’s main international airport. In response, Israel bombed the international airport in Yemen, which serves the capital, Sana, causing extensive damage and destroying the last remaining aircraft used by the Houthi government, Israeli officials said.

The Houthis have retained their ability to hit ships in the Red Sea, and last month they expanded their attacks on Israeli interests there to include vessels at or on their way to the port of Haifa.

“Now the Houthis are the most capable and forthcoming of the axis, but at the same time the strikes have had an impact on their capacity,” said Mr. Ali, the analyst. “We’ve seen a diminishing of their capabilities over the past two years, that should be taken into account in the bigger picture.”