In early 2020, the US Army began the exercise Defender-Europe 20, which involved the deployment of a division-size combat-credible force from the United States to Europe. Up to 30,000 US and allied troops would be involved in this “from fort to port” exercise that from a land forces standpoint, Lt. Gen. Cavioli, commander of US Army Europe, argued, shows how “the demonstration of our collective defence is our best deterrent”.Footnote 31 With this, NATO was flexing its US-based follow-on force muscle that define the core of its ability to conduct major joint operations in Europe. Short of nuclear war, this capacity captures the essence of a NATO deterrence by punishment posture.
NATO had built up this capacity for deterrence by punishment with considerable care since 2014. Enhanced US investment in extended deterrence has formed the backbone hereof. This effort began in 2014 with the so-called European Reassurance Initiative which in the course of 2017 was upgraded to a European Deterrence Initiative, which has allowed the funding of a heel-to-toe presence (i.e., continued but rotational and not permanently stationed troops) of an Armoured Brigade Combat Team with enablers, a Combat Aviation Brigade, an Army Battalion, and a range of supporting infrastructure and exercise investments. What began as a one-year $1 billion emergency response to Russian aggression in 2014 had by 2020 grown into an ongoing $6 billion deterrence program and a primary funding source for the US European command.Footnote 32
NATO allies have complemented this US investment in a number of ways. First of all, they have put more defence money on the table: NATO Europe and Canada invested $313 billion in defence in 2018 compared to $272 billion in 2014. Moreover, in June 2018 they committed to a NATO Readiness Initiative according to which they would have 30 battalions, 30 air squadrons, and 30 naval combat vessels ready to use within 30 days—with the details hereof being worked out through 2020. Also, in 2018, the allies agreed to reform their command structure, re-introducing the North Atlantic command in Norfolk, Virginia, and introducing a new support and logistics command in Ulm, Germany, both designed to secure lines of communications and enable transatlantic reinforcements to NATO’s eastern frontiers. In addition, the reformed command structure gained a Cyberspace Operations Centre, following NATO’s 2016 decision to recognize cyberspace as a domain of operations.
All these measures bolster NATO’s conventional deterrence by punishment posture. The ultimate source of deterrence by punishment is nuclear, and NATO has in this regard undertaken significant but still limited steps. The Alliance revived its nuclear consultations in the course of 2015, including a nuclear consultation exercise based on an Article 5 (collective defence) scenario, and its Warsaw Summit communiqué contained an unprecedented number of references to nuclear forces, even if they mainly rehashed past language of restraint (i.e., “The circumstances in which NATO might have to use nuclear weapons are extremely remote”).Footnote 33 NATO language will have to change and reflect doctrinal adaptation, according to the warning of two prominent analysts: Russian doctrine is premised on the early introduction of nuclear weapons in armed conflict, and NATO must do away with its “extremely remote” doctrine in favour of a “decisive response” doctrine; and this doctrine must underpin NATO’s ability to strike into Russia with conventional weapons to deter a limited Russian “land grab” operation in Estonia or elsewhere, they contend.Footnote 34 In short, NATO has taken steps to reinforce its nuclear deterrence but still has some work cut out at these upper levels of the ladder of escalation.
Deterrence by denial (i.e., an ability to deny Russian objectives by defensive measures) is only possible for NATO at the lower rungs of this ladder, and NATO has not been idle here either. In fact, most of the early measures taken by NATO in response to the annexation of Crimea fall into the deterrence of denial category and centre on rapid reaction capacities, especially in the shape of a NATO Response Force (NRF) upgraded for deterrence purposes. The NRF now has a reinforced, quicker spearhead—a Very High Readiness Joint Task Force potentially up to 13,000 troops strong, and then two complementing brigades with support (each 13,000 strong) forming a layered, sizeable reaction force explicitly linked to collective defence purposes and regularly exercised in Eastern Europe and the Baltic states.Footnote 35 In 2016, in response to the foreseeable difficulties of projecting mainly Western forces into zones of conflicts close to Russia, NATO decided to established an “enhanced forward presence”—four multinational battalion-sized battle groups—in the Baltic states and Poland, and a “tailored forward presence”—mainly naval forces—in the Black Sea region.
Whether these forces can credibly “deny” Russian objectives in the case of limited war is a bone of contention. Most observers and sometimes NATO itself employ the descriptor “tripwire” to these forces, thus indicating that they are triggers that promise to unleash NATO’s big guns and therefore part and parcel of deterrence by punishment. However, US diplomats (interviewed on background) feel more confident that the US battalion embedded (in Poland) in the collective forward presence posture would actually be able to fight and survive, and thus deny Russian objectives. That may be so, in which case the conclusion is that NATO has a moderate-to-low—and geographically focused—capacity for deterrence by denial and then a more general and impressive capacity for deterrence by punishment.
NATO’s unquestionable capacity for deterrence by denial is rather found at the level of grey zone, non-kinetic conflict. In this regard, NATO has upgraded not only its cyber defences and enhanced intelligence coordination, as mentioned, but has enhanced coordination with the European Union on hybrid threats, with a 2016 joint declaration leading to a common work program and a collaborative Centre of Excellence for Countering Hybrid Threats, located in Helsinki, the 2016 adoption of societal resilience benchmarks that, while mostly falling outside NATO’s political-military remit, nations must meet, and finally the decision in 2018 to organize counter-hybrid support teams that can tailor assistance to individual allies and circumstances.Footnote 36
NATO’s full range of actions in response to Russia’s 2014 annexation of Crimea—a range to which this brief overview can do only limited justice—thus combines deterrence by denial (grey zone conflict, societal resilience, reaction and forward deployed forces to counter limited land grabs) and deterrence by punishment (the full chain of reaction and deployable forces, from conventional to nuclear). NATO’s strong suit is the military piece of this posture, but it has considerably adapted to grey zone conflict scenarios in an effort to achieve a comprehensive deterrence posture vis-à-vis Russia’s unified (kinetic and non-kinetic) and uninterrupted (all domains, in war and peace) doctrine of “new generation warfare”.Footnote 37