After Prime Minister Narendra Modi announced the launch of Mission Sudarshan Chakra in his Independence Day speech, Chief of Defence Staff General Anil Chauhan Tuesday (August 26) elaborated on it.Mission Sudarshan Chakra is India’s plan to develop an air defence system on the lines of Israel’s famous Iron Dome. CDS Chauhan, speaking at an event at the Army War College in Mhow, said, “I think it will entail the development of robust infrastructure and processes for the detection, acquisition, and neutralisation of the enemy’s air vectors, including the use of soft kills and hard kills, both kinetic and direct energy weapons,” he said.Chauhan also said that a “colossal amount of integration” will be required, as multiple fields will need to be networked to provide a fused picture.Let’s unpack his comments to understand how air defence works, and what Mission Sudarshan Chakra will require.What is Mission Sudarshan Chakra?According to a government press release, under this mission, “by 2035, critical national sites will be equipped with cutting-edge technology and powerful weapon systems. The mission aims not only to neutralise enemy attacks but also to deliver impactful counterstrikes, much like the Sudarshan Chakra. This step will prove to be a milestone in making national security impregnable and enabling targeted strikes against adversaries.”Basically, Sudarshan Chakra will be a system of surveillance equipment, jammers, sirens, radars, weapons etc., which will identify aerial threats and strike them down before they can attack any Indian site. Its name derives from the discus wielded by Lord Vishnu.What will this entail?At a basic level, “neutralisation of the enemy’s air vectors” involves first intercepting an incoming threat (missiles, bombs, drones, etc.), raising an alert about the threat if necessary, and then acting to disable the threat. If we go back to CDS Chauhan’s statement, he talks about “the use of soft kills and hard kills” and “both kinetic and direct energy weapons.”Story continues below this adSoft kill means using a cyber measure to jam or misguide an incoming threat, and hard kill means physically destroying the threat. A kinetic weapon uses the force of its own movement to destroy a target — for example, a missle comes at great speed and slams into the intended target. On the other hand, a direct energy weapon involves directly focusing energy onto a target, like throwing a laser beam on to a drone to disable it.Another vital element in air defence is of course offence, where the enemy’s strike capabilities are destroyed proactively before an impending attack.All of this requires a lot of coordination, among intelligence gathering, data collection and analysis, strategy, and ultimately, action.The CDS said, “We’ll have to look at multi-domain ISR, integration of ground, air, maritime, undersea, space, sensors, all becoming a key necessity and integrating them.” ISR here refers to Intelligence, Surveillance, and Reconnaissance.What steps have been taken towards this?Story continues below this adOn Sunday (August 24), the Defence Research and Development Organisation (DRDO) successfully conducted the first flight-tests of an indigenous Integrated Air Defence Weapon System (IADWS). The test was conducted off the coast of Odisha, in which three different targets were simultaneously destroyed at different ranges and altitudes.The IADWS is a multi-layered air defence system, which includes three components — Quick Reaction Surface to Air Missiles (QRSAM), the advanced Very Short Range Air Defence System (VSHORADS) missiles, and a high-power laser-based Directed Energy Weapon (DEW).And what is Israel’s Iron Dome?Whenever air defence is discussed, the Iron Dome often comes up. The Iron Dome is a short-range, ground-to-air, air defence system that includes a radar and interceptor missiles, which track and neutralise rockets or missiles aimed at Israeli targets. It is used for countering rockets, artillery and mortars as well as aircraft, helicopters and unmanned aerial vehicles.After the 2006 Israeli-Lebanon war, when the Hezbollah fired thousands of rockets into Israel, the country got to work on protecting itself against aerial threats. The Iron Dome was deployed in 2011. While it is the most famous, the Dome is only one layer of Israel’s air defence network.Story continues below this adIsrael also has David’s Sling and the Arrow systems, whose range is longer than the Iron Dome, which means they can intercept targets further away. Then is the Iron Beam, which is short-range, but uses laser beams to destroy targets and is thus cheaper than traditional defence systems.