The Collective Security Treaty Organization (CSTO) was established on 15 May 1992 after Russia's initiative and can be considered the ideological heir to the Warsaw Pact, albeit of a considerably lesser quality. Russia was aware that the previous military bloc it headed has come to its end, so it was required to establish a new one in order to stand against NATO. Thus, the CSTO was created but it can't be considered a significant military bloc.
The following countries are CSTO members: Russia, Tajikistan, Kyrgyzstan, Kazakhstan, Belarus and Armenia.1 None of these countries, with the exception of Russia, can be considered independent, i.e. the economic and military potential of all the other CSTO member states is intended for the sole purpose of supplementing Russia. This means that the organizations works in Russia's interests.
In addition to the CSTO, many former Soviet republics joined the Commonwealth of Independent States (CIS) - another pocket organization of Russia. This brings us to the most interesting part - the possibility of resolving the Nagorno-Karabakh conflict or, to be more precise, the unresolving of the conflict or selfmate.
Which are the states most directly involved in the Nagorno-Karabakh issue? Undoubtedly, Armenia and Azerbaijan, but Russia and Turkey are also key players in all of this.
Let's begin by looking at the relations between all the engaged countries.
First, Armenia and Azerbaijan. The territorial dispute between both nations rules out the possibility of establishing any sort of peaceful relations. It would be more precise to say that both countries hate each other. But it is quite extraordinary that both of them are CIS member states. That is the true definition of a commonwealth.
Next, we have Russia-Armenia and Russia-Azerbaijan. Russia and Armenia both are part of the CSTO, CIS and the Eurasian Economic Union, while Russia and Azerbaijan share membership only in the CIS.
This means that Russia should have closer ties and cooperation with Armenia, but in reality the situation is the opposite. In 2019, the trade between Armenia and Russia was USD 2.6 billion, while the trade between Azerbaijan and Russia reached USD 3.2 billion. This means that Russia trades less with the country that it has closer cooperation with than with the country with which it doesn't have such a close cooperation.
Now comes the most interesting part - Russia has signed several military cooperation agreements with both countries and is supplying armaments to both Armenia and Azerbaijan.
This is a table comparing Russian armaments deliveries to both countries in the last ten years:2
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