The U.S. and Russia implemented a cease-fire in a limited area of southern Syria last month; the two countries are reportedly in talks about how to de-escalate the conflict elsewhere. According to Yossi Kuperwasser, the agreement “tacitly gave legitimacy to the prolonged presence of Iranian and Iranian-backed forces” in much of Syria. Israel is concerned that further agreements will do the same—and that Tehran will begin using Syria as a conduit for sending arms, supplies, and troops to Hizballah. Kuperwasser points out other, even more troubling, consequences:

Iran almost assuredly wants to turn Syria into an Iranian military base. It plans to build a naval base [on the coast], and may move ground forces, missiles, and maybe even aircraft there as well so that instead of threatening Israel from 1,300 kilometers away, Iranian forces could sit on Israel’s doorstep. This would bring about a dramatic change in the nature of the threat Israel is facing. In fact, Israel’s neighbor to the north would no longer be Syria but Iran, using a Syrian façade with impunity. . . .

The Iranians may [also] take advantage of their continuous presence in Syria . . . to make progress on Syrian territory in their nuclear program. Under the 2015 nuclear deal, the International Atomic Energy Agency can monitor nuclear activities in Iran, but has no authority to monitor Iranian activity abroad. . . . Iran may use [such] loopholes to conduct research and development of nuclear-related material in Syria.

As a reminder: ten years ago, Syria nearly completed a secret nuclear facility in Deir Ez-Zor with Iranian and North Korean assistance. The facility was destroyed [by Israel] in September 2007.

The Russian interest in this negotiated deal reflects the Russian commitment to keep Bashar al-Assad as president of Syria and to secure the ongoing presence of Russian military bases in Syria. Russia regards Iran as an irreplaceable protector of Assad. Putin is also motivated by the Russian interest in weakening radical Sunni forces that constitute the most effective elements of the opposition to Assad. . . . A continuous Iranian presence in Syria is a strategic interest for Moscow.

Early Friday morning, Israel attacked military installations near the Iranian cities of Isfahan and nearby Natanz, the latter being one of the hubs of the country’s nuclear program. Jerusalem is not taking credit for the attack, and none of the details are too certain, but it seems that the attack involved multiple drones, likely launched from within Iran, as well as one or more missiles fired from Syrian or Iraqi airspace. Strikes on Syrian radar systems shortly beforehand probably helped make the attack possible, and there were reportedly strikes on Iraq as well.

Iran itself is downplaying the attack, but the S-300 air-defense batteries in Isfahan appear to have been destroyed or damaged. This is a sophisticated Russian-made system positioned to protect the Natanz nuclear installation. In other words, Israel has demonstrated that Iran’s best technology can’t protect the country’s skies from the IDF. As Yossi Kuperwasser puts it, the attack, combined with the response to the assault on April 13,

clarified to the Iranians that whereas we [Israelis] are not as vulnerable as they thought, they are more vulnerable than they thought. They have difficulty hitting us, but we have no difficulty hitting them.

Nobody knows exactly how the operation was carried out. . . . It is good that a question mark hovers over . . . what exactly Israel did. Let’s keep them wondering. It is good for deniability and good for keeping the enemy uncertain.

The fact that we chose targets that were in the vicinity of a major nuclear facility but were linked to the Iranian missile and air forces was a good message. It communicated that we can reach other targets as well but, as we don’t want escalation, we chose targets nearby that were involved in the attack against Israel. I think it sends the message that if we want to, we can send a stronger message. Israel is not seeking escalation at the moment.