What is it?

• S-400 Triumf is one of the world’s most advanced air defence systems that can simultaneously track numerous incoming objects — all kinds of aircraft, missiles and UAVs — in a radius of a few hundred kilometres and launch appropriate missiles to neutralise them.
• It is now bang in the middle of the ongoing stand-off between Russia and Western nations. Among the countries under pressure from the U.S. not to buy this weapon is India.
• The system is a large complex of radars, control systems and different types of missiles.
• The highly automated S-400 has radars that can pick up an incoming object up to a 1,000 kilometres away, track several dozen incoming objects simultaneously, distribute the targets to appropriate missile systems and ensure a high success rate.
• The command post detects, tracks and identifies the target.
• Then the tracked object is taken over by manned anti-aircraft missile systems of the complex, which launch the counter attack.
• The development of S-400 (NATO name SA-21 Growler) was started towards the end of the Soviet Union in the 1980s and was disrupted by the collapse of the Communist bloc in 1991.
• The system is specifically designed to detect and destroy an array of targets — strategic bombers; aircraft used for electronic warfare, early warning, and reconnaissance; fighter jets such as F-16 and F-22; and incoming missiles such as Tomahawk.
• Russian forces have deployed at least half-a-dozen S-400 regiments, at least two of them are for the protection of Moscow.
• Russia has also deployed at least two S-400 systems in Syria, much to the concern of observers who fear the system could contribute to a global conflict breaking out in Syria. 

How did it come about?

• S-400 traces its origins to the desperation of the Cold War period to find a credible counter to the threat from missiles and incoming enemy aircraft. S-400 is a dramatic improvement from its predecessor S-300, which was the mainstay of Soviet Union’s air defence during the Cold War, when nuclear missile threat was at its peak.
• S-300 was initially developed against incoming cruise missiles and aircraft, but the latter versions could also intercept ballistic missiles. They were deployed in the 1970s across Soviet Union for protecting key industrial complexes, cities, and other strategic assets.
• Today, the S-400 uses four different types of missiles and can track and shoot down incoming objects as far away as 400 kilometres, while it also has shorter-range missiles to track and shoot down objects that are closer.

Why does it matter?

• The acquisition of S-400 by countries such as India and Turkey has taken centre stage in the American diplomacy regarding Russia. Upfront, the recent sanctions against Russian entities, especially its military manufacturers and suppliers, mean any country buying the system may run into trouble.
• Besides, the U.S. has singled out the acquisition of S-400, telling potential customers such as India and Turkey that it is opposed to the move. It believes that S-400 could access sensitive U.S. military technologies in service with the potential buyers. Congressman Mac Thornberry, Chairman of the U.S. House Armed Services Committee, during a recent visit to New Delhi, said: “There is lot of concern in the U.S. over the S-400 system. There is concern that any country, and not just India, that chooses to acquire the system will make it harder to have the level of interoperability we want to have.”

What next?

• Defence Minister Nirmala Sitharaman on Friday said the negotiations for the S-400 were in a “conclusive stage.” There are conflicting reports about Turkey’s plan. American diplomats have accused Russia of “flipping” Turkey with the S-400 offer, while Turkey claims it is a defensive system. At the NATO summit in Brussels early this week, Turkish Foreign Minister Mevlut Cavusoglu said the first batch of the S-400 system would be in Turkey by late 2019.