The power of nuclear submarines lies in two aspects. On the one hand, it has good concealment. Nuclear submarine is a kind of submarine, which refers to a submarine designed with nuclear reactor as its power source. Its underwater endurance can reach 200,000 nautical miles, and its self-sustaining power can reach 60-90 days, which enables nuclear submarines to quietly stand by in the vast sea areas of the world or reach the designated attack position one or two months in advance. On the other hand, its powerful weapon carrying capacity and the combination of nuclear submarines and nuclear strategic missiles make the development of submarines enter a new stage, and nuclear submarines equipped with nuclear strategic missiles are the nuclear forces of underwater deterrence. In other words, the most powerful thing about nuclear submarines is that they are always on standby in the vast ocean. It can be used for both nuclear attack and nuclear counterattack, and it is an important strategic deterrent force. At present, there are six countries in the world that openly claim to have nuclear submarines, namely the United States, Russia, Britain, France, China and India (India's nuclear submarine destroyers are under construction). Among them, the United States and Russia have the most nuclear submarines.

As early as the 1950 s, the Soviet Union began to provide military assistance to India. 1In February, 967, India introduced the first batch of submarines from the Soviet Union, which marked the formation of the Indian Navy submarine force. After that, India introduced Soviet submarines many times. After the disintegration of the Soviet Union, India and Russia continued to maintain close military cooperation. The three armed forces are equipped with a large number of equipment imported from the Soviet Union/Russia. As early as 1988, India leased the 670 "ray" class cruise missile nuclear submarine of the former Soviet Union and renamed it "Chakara", 20 1 12. According to the news of Indian media "India", Russia and India actually had contact and negotiation on the lease of this nuclear submarine very early, and India has tentatively named this nuclear submarine as "chakra -3".

Russia leased nuclear submarines to India for the following reasons:

First of all, it is determined by the contradiction between India's great power strategy and insufficient domestic manufacturing capacity. India has always had the ambition to become a big country with international influence, and has also been facing strategic pressure from Pakistan and China. It is the dream of several generations in India to establish a trinity strategic deterrent force. After renting the nuclear submarine for the first time, the domestic ballistic missile nuclear submarine "destroyer" was built, but this kind of nuclear submarine could not meet the demand of India at all, and the new nuclear submarine plan could not be realized for a long time. India urgently needs to acquire nuclear submarines in the international market. Among the countries that can manufacture nuclear submarines in the world, Britain, as the former colonial sovereign of India, has historical burdens; France has great interests in North Africa. Once India completely controls the Indian Ocean, France's interests will suffer. There are various problems between China and India, and it is impossible to give India any opportunity to develop its strategic strength; America is the leader of the global order. It is its core interest for as few countries as possible to acquire strategic weapons to stabilize the global order, and it is impossible to help India acquire strategic capabilities. Russia is India's only chance to acquire a nuclear submarine.

Second, the tradition of Soviet-Indian military cooperation since the former Soviet Union. From Soviet-Indian relations to Russian-Indian relations, the two countries have always maintained friendly cooperation. Leasing nuclear submarines to India plays an important role in maintaining and consolidating friendly relations between Russia and India. Russia's leasing of nuclear submarines to India without violating international law will not cause opposition from the international community, but will also bring Russia a lot of foreign exchange income.

Finally, there is no potential strategic confrontation risk between Russia and India. Since the disintegration of the Soviet Union, there is no possibility of conflict between Russia and India in geostrategy, and there is no historical burden. There is no risk of conflict and confrontation in the economic field, global security strategy field and international leadership, and Russia's leasing of nuclear submarines to India will not endanger its strategic interests. However, leasing nuclear submarines to India can gain many strategic benefits for Russia. First, Russia can strengthen Russia-India relations and gain influence in the Indian Ocean. Secondly, Russia can increase its chips in the game with China. A strong Indian will make China need Russian more. When necessary, Russia can use its Indian support as a bargaining chip with China. Finally, it is to prevent India from fully falling to the United States. If India falls to the United States, Russia will not only lose a partner, but also add a potential enemy.