Research Brief

As part of its post–Cold War strategy, NATO has embarked on the twin processes of enlargement and transformation. The first round of post–Cold War enlargement occurred in 1999, with the accession of Poland, the Czech Republic, and Hungary. NATO's transformation also dates from the 1990s, when the alliance, while reaffirming its commitment to the collective defense of its members, expanded its mission to include conflict prevention and conflict management throughout Europe, including areas outside the boundaries of the NATO treaty area. Both NATO's enlargement and its transformation have been driven primarily by political imperatives, that is, by an environment-shaping agenda of democratization and integration rather than threat-based military rationale. There is good reason to believe that the two processes have been a major cause of the benign security environment that has prevailed in Europe since the second half of the 1990s, an environment characterized by the absence (or extremely low incidence) of armed conflict and the lack of near-term potential for a major war. To a large extent, NATO's enlargement and transformation have functioned, respectively, as the proverbial carrot and stick. The enlargement offers a positive incentive for peaceful and cooperative relations in Europe, while the transformation holds out a negative incentive in the form of the alliance's commitment to enforce peace and deter aggression, as demonstrated in the 1999 Operation Allied Force against Yugoslavia.

The prospect of NATO's continuing enlargement has important military implications, which are examined in NATO Enlargement 2000–2015: Determinants and Implications for Defense Planning and Shaping, a new RAND report by Thomas S. Szayna. The study provides an analytical framework for thinking about the determinants of future enlargement, the defense challenges posed by the integration of new members, and the strategies needed to respond. One challenge for defense planning lies in the fact that NATO, by taking on a larger responsibility for European security as a whole and identifying specific countries as possible future members, has extended implicit and conditional security guarantees to many nonmember states. A second challenge arises from the difficulty of integrating the military forces of potential new members, particularly former communist states, into the alliance. Membership in NATO entails a special level of cooperation, trust, and specific preparation for joint operations and, because the credibility of NATO's collective defense commitment is at stake, new and potential members have to achieve high levels of interoperability with the alliance. To facilitate the integration of new members, the United States and its NATO allies can use their influence to help shape the choices made by potential members in developing and transforming their armed forces.

NATO Has Explicit and Implicit Criteria for Considering Accession of New Members

As a first step to understanding the specific defense challenges posed by new members, the RAND study employed an analytical framework to assess the likelihood of accession for prospective member states. A total of 12 countries are conceivably candidates for membership in NATO in the next 15 years, although only a few of them are actually likely to join NATO in that time frame. Nine countries have been identified by NATO as being on track to membership through the Membership Action Plan (MAP). The other three potential members are European Union (EU) members not currently in NATO; depending on the evolution of internal debates in these countries, any or all of them could decide to seek NATO membership during the next 10–15 years. Szayna assessed the likelihood of membership for the 12 countries according to the political, economic, and military preconditions for membership outlined by the alliance as well as the implicit, but no less important, strategic rationale for NATO to invite a particular country to join the alliance. All of these criteria played a role in the process leading to the 1999 enlargement. In the study, prospective members were first evaluated according to a scale constructed to match the five main preconditions for membership outlined by NATO in its 1995 study on enlargement:

  • a functioning democratic political system,
  • democratic civil-military relations,
  • treatment of minority populations in accordance with democratic governance,
  • a functioning market economy, and
  • the ability to make a military contribution to the alliance.

The resulting assessment was supplemented by an analysis of the strategic costs and benefits entailed by a given country's accession to NATO. Each country's strategic position was assessed according to four criteria:

  • relevance to NATO's ability to project power in areas of likely contingencies,
  • creation of interior and easily defensible borders within the alliance,
  • risks that may accrue from a higher level of commitment to a new ally, and
  • added transaction costs of a new member for the alliance's cohesion and ability to perform its main missions on the basis of consensus.

Current and Prospective NATO Members

The military forces of prospective members also were assessed according to each country's ability to contribute to power projection missions and sufficiency for deterrence and border defense. The prospective members analyzed in the study, along with current NATO member states, are shown in the figure.

Using the criteria outlined above, these findings emerged regarding the "long list" of potential NATO members: Of the MAP states, Slovenia and Slovakia largely meet the criteria outlined by NATO and their accession poses no major strategic problems for NATO. Estonia, Lithuania, and Latvia are advanced in terms of meeting NATO's preconditions, but the strategic ramifications of their accession loom large. Bulgaria and Romania have the opposite problem of being unable to meet NATO's preconditions, even though the strategic implications of their accession are not problematic. Macedonia and Albania are least advanced in meeting NATO's preconditions and their prospects for membership are distinctly long term. Of the European Union members currently not in NATO, Austria is in good position to join if it chooses to do so. To a lesser extent, so is Sweden. Finnish membership, however, would entail some difficulties because of the strategic cost it would impose on NATO.

The assessments just described are in no way permanent. They are based on the current state of internal post-communist transformation in the MAP states and on NATO's contemporary focus of attention on the Balkans. The assessments are subject to considerable uncertainty, particularly in the event of an unexpected shift in the security environment that currently prevails in Europe.

Most of all, the assessments above are not policy recommendations on which members should or should not be invited to NATO. Instead, they are a necessary first step for thinking about a long-term shaping strategy regarding the MAP countries and the specific activities that the strategy may entail for NATO, the U.S. European Command, and its service component commands.

Aspiring Members Pose Significant Defense Challenges for NATO

The RAND study analyzed the current status and future direction of the reform of the armed forces in prospective member countries. All MAP countries face challenges in their attempts to reshape their military forces. The main problems are:

  • Low technological sophistication and training and readiness levels. Over the next 10 to 15 years, individual MAP states have the potential to make only minor (though not irrelevant) military contributions to the alliance in terms of collective defense and power projection.
  • Limited defense budgets. For the foreseeable future, the defense budgets of the MAP states (except for that of Slovenia) will be much smaller than those of current NATO members of similar size.
  • Acute problems with air forces and air defense. The armed forces of only three MAP states (Slovakia, Romania, Bulgaria) have experience with advanced (fourth-generation) combat aircraft, and even these air forces provide inadequate training to air crews (by NATO standards); the others currently possess little equipment of any kind and lack the ability to ensure their own air sovereignty.

From a defense planning perspective, one of the most significant issues for the United States and its NATO allies is the paradoxical relationship between a country's likelihood of joining NATO and its need for security. The MAP countries least likely to join NATO in the near term cannot provide much of a deterrent in the event of an unexpected crisis, and, as a result, are most in need of NATO's security guarantee, a situation that is likely to continue for a considerable length of time. In contrast, those countries most likely to join are least in need of the security guarantee.

The United States and Its Allies Can Help Shape the Armed Forces of Prospective Members

The process of integrating the armed forces of the MAP states into NATO will be long and difficult, but these problems are neither insurmountable nor unexpected. With a well-thought-out long-term plan of development, wise investments in modernization, and increased operations and maintenance spending, the armed forces of the MAP states eventually could make a meaningful, if small, military contribution to NATO, on a par with that of many current members. This is where NATO's shaping incentives come into play. The alliance can help shape the choices the aspiring members make in their plans toward greater efficiency and effectiveness.

Indeed, NATO is in a good position to help shape the development of the armed forces of the MAP states to the benefit of both the alliance and the prospective members because the prospect of NATO membership serves as an inducement to the prospective members to adjust to NATO's preferences regarding force development. The MAP states stand to contribute more to NATO if, instead of building up their forces across the board, they build on existing strengths and focus on the prospective missions their armed forces might undertake. Greater specialization, with an emphasis on ground forces, will provide prospective members with a stronger deterrent and a lower likelihood that NATO will be called on to provide assistance and reinforcement. Although the alliance does not have the same level of influence over the force plans of non-NATO EU members (Austria, Sweden, Finland), NATO can nonetheless encourage these countries to maintain and develop their forces in a way that would allow for easy integration into NATO at a future date.

An appropriate strategy for the United States toward the MAP states should be individually tailored to each country while incorporating an understanding of five key issues:

  • the potential strategic exposure and need for NATO reinforcement that accompany hypothetical threats to a MAP state under crisis conditions;
  • the time frame for a MAP state likely joining NATO;
  • the severity of the problems a MAP state faces with its armed forces;
  • the means available to a MAP state for addressing the problems of its armed forces; and
  • the likely useful (technologically sophisticated and well-trained) contribution of a MAP state to NATO's peace operations.

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