So far it seems that the dual-track, carrot-and-stick approach of trying to isolate Iran by combining UN and EU sanctions with the offer of dialogue and economic and political incentives has not been successful. Many analysts now agree that the window of opportunity for reaching an agreement before Iran develops a credible and secure breakout option is closing. As Iran’s nuclear and missile program progresses it is becoming increasingly necessary to recognize the military dimension of the dispute. In order to increase the pressure on Iran, NATO should finally acknowledge the country’s nuclear and missile programs as an evolving risk to alliance security.

Since 2002, all attempts to resolve the issues with Iran have yielded little success. In addition to six UN Security Council resolutions, four of which impose sanctions on the country, the EU increased the political pressure on Tehran by imposing severe economic sanctions. The impact and leverage of EU sanctions cannot be underestimated—a 10 percent devaluation of Iran’s currency and an increase of fuel and food prices are a clear indication of their effectiveness. Although the EU3+3 met with an Iranian delegation four times in 2012 to develop a framework for a negotiated solution, no breakthrough was accomplished.

Following its reports in November 2011, the International Atomic Energy Agency (IAEA) has continued to express growing concern about the possible military dimension of Iran’s nuclear activities. The IAEA has been unable to solve outstanding issues with Iran despite several meetings this year. In its latest report from August 2012, the agency assessed that Iran’s uranium enrichment capability is progressing, and the base material for the production of weapons-grade uranium is growing. Additionally, Iran’s ballistic missile program is slowly but surely bearing fruit. Several NATO members—Romania and Turkey—as well as many of the United States’ regional allies and partners—Israel and several Arab Gulf nations— are already within range of Iran’s ballistic missiles.

In its latest Strategic Concept, NATO emphasized the risk of the proliferation of weapons of mass destruction as a main challenge to alliance security. At the 2010 Lisbon Summit NATO decided to build a territorial missile defense system in order to limit the damage of a possible missile strike from the Middle East on Europe. They announced that the system had reached initial operational capability at the Chicago Summit in 2012. However, until now the alliance has not formally addressed the main sources of concern, which are Iran’s nuclear and missile programs.

NATO’s involvement as an additional player would provide a further instrument to add to the international pressure on Iran and send a strong signal to Teheran that its current policies have consequences. With its involvement, NATO could enhance the chances of a successful carrot-and-stick approach.

The alliance must continue to adapt its language and actions gradually and according to the course of events.

First of all, NATO should emphasize its concern about the proliferation of weapons of mass destruction and their delivery systems, including the unresolved Iranian nuclear dossier. If no negotiated solution can be reached in the foreseeable future, NATO should state that Iran’s nuclear and missile programs are an evolving risk to alliance security. A second step could be alliance consultations under article 4, a principle that was strengthened at the Lisbon Summit and allows any member country to consult if its territorial integrity, political independence, or security is threatened. Finally, NATO can declare that Iran’s nuclear policy is a threat to the alliance and therefore that it must consider Iran in its defense and contingency planning process.

Individual NATO members have repeatedly stated that a nuclear Iran is unacceptable. An unequivocal statement by the alliance itself would show solidarity with those NATO members already affected by the development of Iran’s missiles, and also clearly express the unity and resolve of all 28 NATO members on the Iran issue.

Although NATO has already attempted to make Iran an alliance issue, Turkey has been cautious about identifying the country as a growing concern in official NATO documents. However, unofficially, Iran has repeatedly been the cause of unease in Ankara, and Turkish-Iranian relations have been deteriorating.

Turkey’s contribution to NATO’s territorial missile defense was not received well in Teheran and indicates that Ankara is concerned about the development of Iran’s military capabilities. This was also revealed during the U.S. Nuclear Posture Review in 2010, where the United States intensively debated on the credibility of its extended deterrence for Turkey now that the latter faced a potential nuclear Iran. For that reason, Turkey may now be willing to accept NATO’s involvement in the issue.

Showing resolve might also be a relief for Israel, which is very concerned about the strength of the West’s determination to prevent Iran from obtaining nuclear weapons capabilities. Israel doubts the credibility of President Obama’s message that the United States would not be satisfied with merely containing a nuclear-armed Iran. In addition, although the EU discussed the options for further sanctions on Iran at the latest Foreign Minister meeting in Cyprus, the perspective in Jerusalem is that European countries have never explicitly addressed the military dimension of the dispute. A clear message by all 28 NATO members could reassure Israel, and potentially strengthen the current U.S. position that, albeit little, there is still time for negotiations.

Arab Gulf states are also deeply concerned about the impact Iran reaching the nuclear threshold would have on the balance of military power in the Gulf. Increases in military procurement in the region, such as those by Saudi Arabia and the United Arab Emirates, are a clear indication of that. NATO’s involvement could provide indirect reassurance to Arab Gulf states and therefore reduce proliferation incentives and the pace of the conventional arms build-up.

This is not to say that NATO should consider participating in a pre-emptive strike on Iranian nuclear and missile sites. However, NATO’s involvement could highlight that all its members understand the regional security implications of a virtual or defacto nuclear-armed Iran, and are willing to increase the pressure on Tehran. Consequently, NATO should express its concern about the unresolved issue of the Iranian nuclear dossier. With attempts by the EU3+3, the UN Security Council, and the International Atomic Energy Agency to solve the issue remaining unsuccessful, and Iran’s nuclear and missile programs continuing to progress, the alliance needs to address this evolving risk to its security.

Oliver Schmidt is a doctoral fellow at the International Security Division of the German Institute for International and Security Affairs (SWP) in Berlin.