Vladimir Putin knows how to pack a punch. The combative Russian president, an avid judoka, applies the martial art's two principles to diplomacy. One: move rapidly. Two: use the weight and strength of the opponent to your advantage rather than combating them directly.

In a deft move, Putin closed a $5.4 billion arms deal with India, selling the Russian S-400 Triumf surface-to-air missile defense systems at the beginning of October.

India, bordered by Pakistan's 20 fighter squadrons, and China's 1,700 fighter planes, must "match the force level of our adversaries," the head of India's Air Force has declared.

With this huge deal, Russia has emerged as the winner with the "largest contract" in the history of India-Russia defense ties.

It’s also the "speediest" arrangement to be signed between the two countries unencumbered by "any protracted negotiations."

It's news that Donald Trump would wish is fake. But it isn’t, and he knows it.

Russia, now, commands a competitive edge over its arch weapons industry rivals - the United States and Israel - and is currently India’s biggest arms supplier.

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Russia managed to do this despite the U.S.' attempts to persuade other nations not to buy Russian weapons by threatening to invoke Section 231 of Countering America’s Adversaries Through Sanctions Act (CAATSA) of September 2017.

CAATSA, a U.S. domestic law, empowers the American administration to impose sanctions on countries that engage in "a significant transaction" with Russia’s defense or intelligence sectors.

Citing these sanctions, the United States had tried to dissuade India from buying the S-400 Triumf air missile system from Russia. Months before the deal, Tina Kaidanow, Principal Deputy Assistant Secretary of State for Political-Military Affairs, said:

"We’ve discussed CAATSA with the government of India just as we have discussed it with a number of others who might be potentially contemplating purchase of large defence systems from the Russians. We want to work with all of our partners to help them identify and avoid engaging in any potentially sanctionable activity."

Brushing aside the threat of sanctions, India has repeatedly made it clear to the U.S. that it would go ahead with the S-400 Triumf missile deal with Russia.

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Several Indian delegations, led by the Foreign Secretary, made a case for waiving the sanctions, arguing that the CAATSA is an American domestic legislation with no bearing on India’s decision making. The delegations have also suggested that the CAATSA sanctions would create an unnecessary standoff between the U.S. and India, critical military allies in the Indo-Pacific.

The U.S. Defense Secretary Jim Mattis and the U.S. Secretary of State Mike Pompeo, have acknowledged this concern and strongly advocated the waiver of sanctions on India. But it came with a caveat - that the U.S. "can’t guarantee a waiver will be used for future purchases."

As the State Department clarified: "There are no blanket waivers that will be issued for any one country, and any waiver that we might contemplate for significant transaction with Russia would be assessed on a case-by-case basis and would require, among other things, countries to significantly reduce their reliance on Russian arms."

On October 5, 2018, India stood its ground and went ahead with the purchase of five S-400 missile systems from Russia. It’s a key defense decision that has been coyly underplayed - finding only a brief mention in the India-Russia joint statement, issued after their 19th annual summit between the two countries in New Delhi.

Open gallery view Two missiles fly over the training ground "Tsugol" during the military exercises Vostok 2018 in Eastern Siberia, Russia. Sept. 13, 2018 Credit: Sergei Grits,AP

India is not the only country to buy the S-400 surface-to-air missile weapons systems. In the recent past, other nations have ignored the threat of CAATSA sanctions, and engaged in "significant" transactions with Russia - China purchased Sukoi S35 fighter jets and S-400 surface-to-air weapons systems; soon after, Turkey followed suit and bought four S-400 systems from Russia at the cost of $2.5 billion.

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The United States, keen to throw its weight and show its strength, imposed sanctions on a Chinese entity - the Equipment Development Department or EDD - and its director, Li Shangfu, for purchasing Russian weapons systems.

With this move, the U.S., very successfully, managed to "outrage" China. Reacting to Washington's move, Chinese Foreign Ministry spokesman Geng Shuang said:

"China is strongly outraged by this unreasonable action of the U.S. and lodged stern representations. What the U.S. has done gravely violated the basis norms governing the international relations and harmed the state-to-state and military-to-military relations between the two sides."

But far from moving away from Russia, China has stepped up its military ties with Moscow.

The U.S. displayed its strength by slapping sanctions on China; Russia used it to its advantage - in true judo style. The CAATSA, intended to wean countries off of Russian weapons, isn’t working. Putin’s deft moves render it a paper tiger.

To counter China's growing influence in the Indo-Pacific region, the U.S. needs India as much as India needs the U.S.

Open gallery view Narendra Modi, India's prime minister, and U.S. President Donald Trump at a joint statement in the Rose Garden of the White House in Washington, D.C., U.S. June 26, 2017 Credit: Bloomberg

In the 2+2 Ministerial dialogue between the U.S. and India, held in New Delhi in September 2018, "defense cooperation" has emerged as the most significant dimension of the strategic partnership and the "key driver" of the overall bilateral relationship between the two countries.

As the State Department noted: "The United States declared India a major defense partner in 2016, a status unique to India…We expect progress and further deepening the ties between our two militaries and creating a framework for greater information sharing and interoperability. We are also eager to expand defense trade."

However, a few days after the Russia-India defense deal was signed, when asked if he would waive off the sanctions against India, a defensive Donald Trump grumbled: "India’s going to find out, aren’t they?...Sooner than you think."

Credit: YouTube

Critics point out that it's a typical Trump strategy - create uncertainty to bully your allies and opponents, so that you can negotiate with them by putting pressure on them.

In fact, over the past two years, Donald Trump’s unpredictability and the mercurial nature of the American administration have pushed India to assert its strategic autonomy. Trump and Bolton, with their bullying tactics, have thrust India closer to Russia. A brief look at the India-Russia Joint statement confirms this.

In that statement, India and Russia pushed for a "multilateral world" and noted that "Military and military-technical cooperation between the two countries is an important pillar of their strategic partnership."

They sought a "full and effective implementation of the Joint Comprehensive Plan Of Action (JCPOA) on the Iranian nuclear program" (in which the Trump White House has abrogated its participation), and reaffirmed "equality, mutual respect and non-interference as universally acknowledged norms of international law."

It’s a sharp pushback aimed at the U.S. administration, which is trying to influence India’s internal decision making by telling India not buy oil from Iran and weapons from Russia.

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India and Russia have also reaffirmed the need to sign the Prevention of an Arms Race in Outer Space (PAROS) treaty - one that the U.S. and Israel abstained from signing at the United Nations General Assembly - to "avert a grave danger for international peace and security."

Scholars and critics have applauded India’s decision to buy the S-400, lauding it for reiterating its "strategic autonomy." But in the upcoming weeks, one crucial decision could turn the tables in the India-U.S. relationship. And, that decision needs to be taken by a man "incapable of seeing past his own ego" - Donald Trump.

In trying to display America’s strength, will Trump impose CAATSA sanctions on India? If he does so, he may think that he can bully India into buying more American weapons and negotiate trade deals. But he would risk alienating an ally – and would push India closer to Russia.

If Trump tries to show his strength, he will certainly lose to Putin’s diplomatic judo – and will in effect be constructing a winner's podium accompanied by a lucrative cash prize for a triumphant Russia.

A fellow at the University of Oxford's Reuters Institute for the Study of Journalism and a graduate of the London School of Economics, Shrenik Rao is a digital entrepreneur and filmmaker. Rao revived the Madras Courier, a 232-year-old newspaper, as a digital publication of which he is the editor-in-chief. Twitter: @ShrenikRao