With little fanfare, the Pentagon last week increased the American military presence in northeastern Syria—sending some 100 soldiers and six Bradley fighting vehicles. Jonathan Spyer explains why:

On August 26, four U.S. servicemen were wounded when the vehicle in which they were traveling collided with a Russian military vehicle. The incident took place . . . at the northeastern tip of Syria close to the Tigris River and the border with Iraq. This area lies far east of the Euphrates, and well inside of territory designated as a U.S.-controlled security zone. That is, the Russian presence in the area was itself a provocation. The collision with the U.S. vehicle took place at a time when Russian military helicopters were deployed above the area. It appears to have been deliberately initiated by the Russian force.

This incident reflects a broader pattern. Moscow [believes] that the American presence in eastern Syria lacks a clear strategic [rationale], and hence may be withdrawn if sufficient pressure is applied to it. Moscow wants to see Syria reunited under the rule of President Bashar al-Assad, as a weak and dependent client of Russia. The Kurdish-controlled, U.S.-guaranteed area east of the Euphrates, comprising around 25 percent of the area of Syria, currently stands as a barrier to the achievement of this goal.

The Russians therefore appear to be attempting to whittle away at the American presence, gradually expanding their own area of activities. . . . Parallel to the campaign of harassment, the Russians are seeking, slowly and incrementally, to draw the Kurdish ruling authorities in this area back under their political patronage. . . . The slow-moving contest over the ruins of Syria thus looks set to continue.

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.