Based on a scrupulous review of a large body of documents from the Russian and some foreign archives, for the first time introduced into scholarly discourse, this article contemplates a period in the Soviet Union history, when the influence of the USSR in world affairs reached its maximum. It was a short by historical standards span, when the so-called “collective leadership” headed by Leonid I. Brezhnev, Alexei N. Kosygin and Nikolay V. Podgorny was at the helm of the Soviet state. The authors of the article show that it is unlikely that the transformation of the USSR into one of the superpowers would have been possible if not the US defeat in Indochina. With the aim of proving this premise, the authors have focused on the developments related to one of the turning points of the Cold War – the first half of 1965. In this context, the article closely analyses the course and results of the negotiations between Kosygin and the leaders of the DRV, PRC and DPRK. In fact, it was then, as evidenced by the researched documents, that the Soviet Union turned de facto from an observer into an actual participant in the Vietnam War (and, more broadly, the confrontation with the United States in the Far East) as part of the anti-American coalition of the USSR – PRC – DRV – DPRK. And although the authors are talking about a strategic plan in place – as it happens in real politics – and also in this case, it was born almost by accident, while the genuine masterminds of the geopolitical combination have remained in the shadow of history for many years.