There are some inherent structural limitations on what NATO can do in terms of working with the CSTO. NATO is focused on cooperating with individual countries rather than with organizations. That’s the first and most important factor limiting the possibilities for NATO-CSTO cooperation.
We should keep in mind that NATO isn’t really an organization in the way that we think about organizations. It’s primarily a collection of countries, each with its own foreign policy. And because it has a consensus principle in its decision-making, NATO can only take an action if none of the member countries object to a proposal. NATO operates by the silence procedure, whereby if no country objects to the wording of what the Secretary General offers as the consensus as he has heard it, they are deemed to have consented. If they object to wording, the discussion is reopened until they are satisfied.
In terms of setting up relations with another collective security organization such as CSTO, as far as I know NATO has pretty much never had relations with another such organization. Even back in the Cold War days, when CENTO and SEATO (the Southeast Asian and Central Treaty Organizations) existed, NATO didn’t really interact with them on an organization to organization basis.
So there are some inherent structural limitations on what NATO can do in terms of working with CSTO. NATO is focused on interaction with individual countries rather than with organizations. That’s the first and most important factor in limiting the possibilities for NATO-CSTO cooperation. There may be a greater chance of having individual NATO member countries working with CSTO, perhaps by participating in CSTO exercises, rather than having NATO as a body doing it. That’s not really the way NATO works in general. Many events that are seen in Russia as NATO events aren’t necessarily NATO events at all. For example, western reports on the recent Sea Breeze exercise in the Black Sea are very careful to describe it as either a U.S.-Ukraine exercise in which other countries participated or as a Partnership for Peace exercise. But it’s never described as a NATO exercise. Whereas reporting in Russia or China describes it as a NATO exercise, even though that is not the way the NATO member countries themselves see it.
A second reason is that NATO right now is mostly focused on internal issues. Since the end of the Cold War twenty years ago, NATO has been looking for a new purpose. One path that has been considered is to protect people in neighboring states against mass killings of civilians in internal conflict. This was its role in Kosovo in 1999 and more recently in Libya. The NATO countries have also added a counter-terrorism mission that has brought tens of thousands of its member countries’ soldiers to Afghanistan over the last decade. But there is still a lot of internal debate among NATO members about what its long term focus should be. So I think rather than trying to focus on relations with other such organizations, the NATO countries are mostly focused on working out how its members will continue to make use of the existing NATO structure and procedures. So that’s a second limitation.
The third limitation may be relevant just for the United States, but because of the consensus principle NATO could not establish formal ties with CSTO without the U.S. being part of that consensus. There are still some parts of the U.S. security establishment, not so much in the current administration, but still important people in Washington who see CSTO as a potential way for Russia to extend its dominance over other former Soviet republics. And they don’t want to do anything to legitimize that. Again, I don’t see this as a policy of the current administration at all, but it’s something it has to take into account when it deals with Congress and with public perceptions of U.S. foreign policy. And since NATO-CSTO relations aren’t a high priority, the administration is not going to expend much political capital on this issue. They’d rather pick their battles with Congress on relations with Russia somewhere else, such as missile defense or last year’s New START treaty ratification.
So, those are the three key reasons why the establishment of a formal NATO-CSTO relationship is very unlikely. However, that doesn’t preclude the possibility that some NATO member countries could work with CSTO on particular issues. It is less likely that the United States would do this than some of the European counties given the political constraints discussed above, but it’s not out of the realm of possibility. It’s certainly more likely than some kind of NATO-CSTO partnership.