Could this be one of the reasons why S-400 makes the United States uncomfortable?

New Delhi, Aug 03: Despite the CAATSA sanctions lurking in the corner, India went ahead with the S-400 deal with Russia and in last October, New Delhi signed a USD 5 billion (Rs 35,000 crore) deal with Russia to buy five systems of this missile that NATO calls the SA-21 'Growler'.

The United States seems determined to dissuade India from going ahead with the acquisition of S-400 missile defence systems. The latest nudge from Washington over the S-400 warns of serious implications on India-US defence ties if New Delhi's goes ahead with the deal to procure the lethal missile system from Moscow.

The S-400 Triumph missile defense system is a significant strategic upgrade in India's military hardware. In fact India badly needed such a system given the hostile surroundings and growing capabilities of China and Pakistan.

China has also purchased S-400 missiles from Russia and for that the US has imposed sanctions on Beijing. The US has imposed sanctions on China's Equipment Development Department (EDD), the military branch responsible for weapons and equipment, and its director, Li Shangfu, for engaging in "significant transactions" with Rosoboronexport, Russia's main arms exporter US says that CAATSA is aimed at punishing Russia for its aggression in Ukraine and involvement in Syria's civil war.

CAATSA also seeks to penalise Moscow for meddling in the 2016 US election, something which Russia denies. The US may or may not impose sanctions on India, that is something only time will tell.

There is another aspect to this entire sanctions in the name of CAATSA debate. Is there something else that is making the US impose sanctions on whoever buys S-400 missiles?

One cannot stop thinking that the US is particularly irked whenever any nation buys S-400 missiles from Russia. Is there a specific reason for this? One can only speculate, but the fact remains that US made MIM-104 Patriot, a system comparable with S-400, is losing market to the Russian weapon system across the globe.

Both are surface-to-air systems designed to shoot down aircraft and ballistic missiles. But the S-400 has a longer range than the Patriot, 250 kilometers vs 160 kilometers. An upgrade coming later this year is expected to stretch the S-400's range to 400 kilometers. It also has a more powerful radar that can destroy targets moving twice as fast, and is quicker to set up. While both systems are mounted on trucks, the S-400 can be ready for action in five minutes, compared with an hour for a Patriot battery.

The S-400 is also far cheaper than the Patriot, on a per-battery basis. Again, no definitive conclusions can be drawn from this, but it is something worth considering, as arms lobby in the US is considered very strong. A lot has been written about how arms lobby in the US does influence the political decision making.