Syria’s air defences sent missiles streaking through the sky on Tuesday night, racing to intercept elusive Israeli aircraft. The Israeli air raid, reported by state news agency Sana, was one of almost 1,000 Israeli air attacks in Syria in three years, according to defence analysis firm Janes. The full extent of Tuesday's airstrikes could not immediately be verified, but appeared to focus on ammunition storage sites west of Homs, and possibly the Him Shanshar military installation, according to analysis firm Aurora Intel<em>. </em> The US government said in 2018 that Him Shanshar had been used to store chemical weapons. The Syrian Observatory for Human Rights, a UK-based war monitor, told AFP that "these are the first Israeli strikes in Syria since the recent war in Gaza". The monitor's claim that air strikes targeted multiple governorates could not be verified. The monitor’s view also implies that the Israeli air force was tied down with the war against the Hamas militant group, and subsequently paused Syria operations. Israeli airstrikes in Gaza killed at least 256 people during the 11 day war including 67 children and an unknown number of militants, as Hamas fired 4,000 rockets into Israel killing 12 people, including two children. One Israeli soldier was killed. But during the Gaza war, the Israeli air force continued a campaign to disrupt a developing missile front against Israel in Syria. Syria has become a “pressure relief valve” in the conflict between Israel, Hezbollah, Iran and allied groups who operate alongside the Syrian regime, according to David, an analyst focusing on the region at Aurora Intel, who chooses to withhold his second name. That pressure valve serves as an unspoken arrangement between Hezbollah and Israel to reduce the risk of a war in Lebanon. “A war with Hezbollah will be devastating for Lebanon and Israel. The devastation for Lebanon could only grow if Hezbollah continues to expand,” he said. A conflict with Hezbollah in Lebanon would likely trigger an evacuation of tens of thousands of Israeli civilians, a plan reported by Israeli newspaper <em>Haaretz</em> in 2016, dubbed Safe Distance. The 2006 Israel – Hezbollah war resulted in the deaths of 44 Israeli civilians and around 1,000 Lebanese civilians. As a result of this risk, Hezbollah and its Iran-backed allies maintain an operational status quo in Syria. In Syria, Iran-backed militias, including Lebanese Hezbollah and Iraqi groups such as Kataib Hezbollah, have been assisting Iran’s Islamic Revolutionary Guard Corps (IRGC) in building an arsenal of unguided rockets and Precision Guided Missiles, or PGMs. According to a report by the Institute for National Security Studies, an Israeli think tank, Hezbollah or any group in Syria allied to Iran could use PGMs to target “high-value strategic targets: airports; vital infrastructures: energy (power stations, gas facilities, Haifa refineries) and water sources” in Israel. PGMs could be existing Iran-designed long range missiles, smuggled overland through Iraq into Syria, or unguided rockets fitted with special guidance kits to turn them into precision weapons. The latter option is preferred by Iran, according to an Israeli military report released last year, because the kits are easier to smuggle than the missiles. A growing guided missile arsenal in Syria would complement the estimated 130,000 rockets and missiles that Hezbollah has in Lebanon, an increasing number of which are PGMs. To counter this growing arsenal, the Israelis dedicated aerial reconnaissance assets for monitoring IRGC operations during the conflict. “Squadron 122 have been monitoring Syria throughout the whole Gaza conflict, they have been airborne several times, visible on ADSB,” said David. Israeli Squadron 122 is a “signals intelligence” unit which overflies enemy territory, with the potential to jam enemy radar and locate targets. While these missions were underway, Iran was also stepping up assistance to allies in Syria – perhaps in the expectation that Israel’s capabilities may have been tied up in the Gaza war. “There were at least 14 IRGC-related flights from Tehran to Damascus since the Gaza conflict began. And those are linked to illicit activities. In previous airstrikes conducted by Israel, including in several documented cases, an airstrike has been conducted within 24 hours of one of these IRGC flight’s arrival in Syria. These flights are monitored and are known, also by their status on the US OFAC Sanction Register,” he said. Israel may therefore have been monitoring Iranian transfers of equipment to Tehran's allies in Syria during the Gaza war, waiting for the moment to strike. But can these hostilities go on without escalating and how long can Syria remain the "pressure valve"? Rising tensions across the region could be a factor in a worsening crisis. "Hezbollah leader Hassan Nasrallah mentioned that they are trying to change the equation on Israel so that all of the 'resistance axis' get involved if 'Israel attacks Jerusalem'. This could be the valve starting to close, which in some respect may force Israel's hand. Either way, a war with Hezbollah will be bloody, on both sides," he says.