On February 19, the Syrian regime, Russian and Iranian militias launched their fiercest ever shelling campaign on Eastern Ghouta the opposition’s only stronghold around Damascus. Days ago the regime’s forces and the militias supported by Russian jets started a massive ground operation and they managed this week to divide Eastern Ghouta into two parts. Due to systemic targeting of civilians – a method the regime and its allies often used - more than 650 civilians have been killed since 19 February according numbers compiled by the White Helmets, an aid group.If Eastern Ghouta falls, that inevitably and necessarily will mean two things.The first is that Iran will be the master of Damascus and that means a constant threat to Israel. The second is that USA will lose Syria to Russia. The impact of the Ghouta operation therefore has implications far beyond Damascus. The Iranian intervention in Syria started in the very beginning of the revolution against the Assad regime’s despotism. Through the past years Iran has had the main role in the regime’s ability to withstand the fighting against the opposition and latter with Russia, guaranteed the regime’s restoring vast areas it had lost from the opposition.Iran mainly contributed to seizing the most parts of Damascus countryside, and Quneitra and Daraa’s northern countryside. Now huge number of Iranian troops and militias are near the Israeli border causing a direct and big threat to Israel. Iran also attacked the opposition groups in the Syrian desert and therefore managed to open a road the extends from Tehran to Beirut. Both Iran and Russia want to seize Eastern Ghouta and each one has its own reason.Eastern Ghouta is the last stronghold of the opposition near Damascus. There is a big number of organized fighters there, with no ISIS presence at all, and a very minimal number of Nusra (HTS) fighters. There are estimated to be only 300 Nusra fighters who are not allowed to fight by the other groups.There are three main groups in Eastern Ghouta consist of the following. First, Jaish al-Islam which has about 11,000 fighters. This group fought ISIS, killing many of them and expelling the remainder, and thanks to this action, Ghouta turned to out be the first opposition area to be fully cleaned from ISIS influence. This group also managed to weaken Nusra by putting them under pressure all the time. The second group is Faylaq Rahman, which has about 10,000 fighters. The third main group is Ahrar al-Sham with about 6,000 fighters. None of these groups is considered a terrorist organization internationally. Nevertheless, Russia has insisted that the groups fighting in Ghouta are “terrorists.”Both Russia and Iran want Eastern Ghouta to fall and each one has its own “logical” reasons that they put forward to the media. Because of these reasons, they crudely violated the UNSC resolution 2401 which demanded a cease-fire throughout Syria - especially in Eastern Ghouta.For Russia, if Ghouta falls, it would mean that the whole of Damascus would be under the regime’s control and that will guarantee for Russia a long-term existence in Syria as well as the safety for its bases in the middle of the country and along the coast. Russia does not intend to keep military forces near Damascus but it needs to save the capital and keep it safe for its influence in the area, which extends from Hama to Homs and then westward to Latakia and Tartus, where it has a naval base. Moscow managed to protect the northern areas of this line of control via the Astana talks and the de-escalation agreements it signed with Turkey and Iran. It also stipulated the deployment of Turkish observation points in Idlib. The second reason behind the Russian support for the operation against Ghouta is that if the whole of Damascus falls under the regime’s control, that will give the regime and Russia a strong leverage in political negotiations.Russia already tried to shift Syrian negotiations from Geneva to Sochi so the Ghouta victory, if it happens, will give momentum to the Russian-hosted Sochi talks and makes Russia the director of the “peace process” in Syria.Iran’s agenda in Ghouta is to seize the area and become the actual governor of Damascus and take control of the Tehran-Beirut road that runs near Ghouta. This will guarantee Tehran the power to blackmail Israel and the West comfortably and will give it a leverage for its nuclear program negotiations. At the same time it will facilitate Iran’s plan for demographic change in Syria. It has always aimed to turn Damascus into a Shi’ite capital.The US should be concerned that the fall of Ghouta will put pressure on Dara’a and Syrian rebels in southern Syria. The regime will follow up the Ghouta operation by moving forces south toward Dara’a which is near Jordan. This will threaten US and UK influence in southern Syria and also threaten the Tanf (Tanaf) garrison that the US-led coalition maintains in Syria near the Jordan-Iraq-Syria border. This will restrict American influence and also threaten the area run by the US partners among the Syrian Democratic Forces and the Kurdish PYD east of the Euphrates river.US influence, including the safety and calm, east of the Euphrates is already impacted because Turkey considers the PYD to be a part of the Kurdistan Workers Party (PKK) and a serious threat to Turkey’s national security. Ankara sees this as a threat to its national security and it intends to push back against what it sees as a threat. The example of Afrin shows that the US allies in eastern Syria are not strong enough to resist Turkey’s attacks. We should add to this the possible new cooperation between Turkey and Russia against the PYD. This could incite the Arab majority in Syria against both the US and PYD and will jeopardize the US influence east of the Euphrates.In southern Syria the US and the UK have been supporting the Free Syrian Army rebel groups. The US, Jordan and Russia signed a de-escalation agreement covering southern Syria in 2017. This relieved pressure on Iran’s influence and forces in Dara’a and Quneitra. Israel has responded to this through intermittent strikes over the past years to prevent Iran extending its influence. But this has proved useless in stopping Iran.If Washington and Israel are not able to move to defend Ghouta or at least secure the southern part of Syria, it will cost them dearly because the defeat of Ghouta will cause the US to lose credibility in Syria among opposition groups. The US will be without a partner in Syria among the rebel groups and even air strikes on Iran and regime positions will be seen as fruitless and a violation internationally. As a result, regardless of the massacres committed by the regime, Russia and Iran; their violations of the Security Council resolutions, is itself is a reason to intervene. An urgent intervention now to stop Iran strengthening its bases and Russian hegemony in Syria has turned out to be a must for Israeli security and American interests.