The credibility of NATO’s deterrence posture rests heavily on the solidarity and cohesion of the Allies. A potential adversary is more likely to refrain from aggression if he believes—as Article 5 of the Washington Treaty states—that the Allies will indeed consider an armed attack against one or more of them to be an attack against them all.
But in recent years Alliance cohesion has been weakened and NATO’s credibility has thus become frayed. Much of the blame can be laid at the door of Donald Trump. Even though his administration has invested in the security of NATO’s eastern Allies through the European Deterrence Initiative, Trump has repeatedly cast doubt on his administration’s commitment to collective defence and castigated individual Allies. Two former US ambassadors to the Alliance have claimed that Trump’s lack of leadership has left NATO in crisis, while Polish and Baltic officials, usually careful not to rock the boat, have expressed concerns about his presidency’s negative impact on the transatlantic relationship.
Even without Trump sowing dissent, however, NATO would be struggling with internal disagreements that put solidarity at risk. Enhanced Forward Presence has been a notable success, but elsewhere the Allies have found difficulties in agreeing priorities or coming to common views on threats. They have pushed parochial interests at the expense of the common good and freelanced on security policy initiatives outside the Alliance, without consultation. And they have allowed disagreements beyond the scope of NATO to sour relationships inside the Alliance. France’s efforts to pursue greater European strategic autonomy and President Macron’s push for a new settlement with Russia have, for example, been met with scepticism and suspicion by many Allies.
Turkey, though, has stood out in its aggressive pursuit of its own interests without apparent concern for the views of or impact on other Allies; to the extent that some officials are publicly (if anonymously) arguing that NATO urgently needs to address its “Turkey problem”. Turkey has defied its Allies in the EU by intervening militarily in Syria and has clashed with Greece, Italy and especially France over its involvement in the Libyan conflict. It has purchased S400 missile defence systems from Russia, a move that saw it expelled from the US-led F-35 joint strike fighter programme. It has blocked the implementation of NATO’s Eagle Defender defence plan for the Baltic states and Poland in an effort to coerce the Allies into recognising the Kurdish YPG militia in northern Syria as a terrorist organisation. Turkey’s drilling for gas off Cyprus and other Greek islands, which the EU has criticised but which Turkey claims is inside its own continental shelf and therefore lawful, has also been a cause of much tension outside and inside NATO.
Under Recep Tayyip Erdoğan, Turkey has become increasingly authoritarian and nationalistic. The drilling operations in the eastern Mediterranean are expressions of the ‘blue homeland’ (Mavi vatan) maritime strategy, which aims to ensure Turkey’s control of the seas that surround it, enhance regional and international influence and secure independent energy sources. This strategy has been accompanied by the development of a larger and more modern navy, muscle that Turkey now seems ready to flex.
Inevitably, Turkey’s blue homeland ambitions have clashed with the interests of other Mediterranean powers. The longstanding Greek-Turkish dispute has become inflamed. France has sided with Greece. But recent events have taken a more dangerous turn as military assets have become involved. In July, a French ship taking part in NATO’s Operation Sea Guardian and attempting to inspect a cargo ship for arms smuggling was targeted by the weapon systems of escorting Turkish ships, leading to France’s withdrawal from the operation (Turkey has denied the details of the incident and asked NATO to investigate). And last week, in response to Greek-Turkish tensions over drilling operations, France announced that it would temporarily increase its military presence in the eastern Mediterranean, including by deploying an additional frigate and two Rafale fighters, to “monitor the situation in the region and mark its determination to uphold international law”. French forces also exercised with their Greek counterparts on the island of Crete.
Raised tensions, disputed narratives and military assets are clearly not a good mix, risking a military incident between two or more Allies. More broadly, a divided Alliance is a weak Alliance, presenting adversaries with opportunities for mischief-making. But without effective leadership from its largest member, NATO has few options for dealing with this situation beyond urging restraint in public and talking behind closed doors in Brussels. Consensus decision-making, one of the Alliance’s core strengths in building cohesion and solidarity to face the outside world, can also be a weakness when it comes to dealing with disputes between Allies. The group of experts supporting the NATO Secretary General’s reflection process, tasked with offering recommendations “to reinforce Alliance unity, increase political consultation and coordination between Allies, and strengthen NATO’s political role,” should certainly turn their minds to this thorny issue.