Throughout much of its existence, NATO has faced a significant challenge: a shortage of troops.

This concern was particularly pronounced during the Cold War, as NATO observed the Warsaw Pact’s 6 million troops stationed in East Germany, compared to their own 5 million, along with a greater number of divisions, tanks, combat aircraft, and submarines.

Since that time, the situation has only deteriorated. In the 1990s and 2000s, NATO member states reduced their troop numbers and adapted their military equipment for two decades of operations in the Middle East. By 2014, when Russia deployed forces to the Crimean Peninsula, the U.S. presence in Europe had dwindled to approximately 30,000 troops. Pentagon officials were compelled to devise strategies to project a force that appeared tenfold larger to deter Russian aggression.

“NATO essentially neglected its military capabilities,” remarked a senior diplomat from a NATO country, who requested anonymity to discuss military strategies. “It was completely inadequate for a major crisis.”

As NATO formulates its new defense strategies to counter a potential Russian offensive from three directions—north, central, and south—it is mobilizing tanks, artillery, and ammunition. However, it is encountering difficulties in securing sufficient troop numbers and is compelled to reevaluate its approach to troop deployment from allied nations.

NATO, primarily under the leadership of the United States, has been relying on all-volunteer forces for the last fifty years. However, in the U.S., all eligible males are required to register with the selective service in case Congress or the President decides to implement a draft.

The recent decline in unemployment rates in the U.S. and Europe has complicated recruitment efforts. Since the onset of the coronavirus pandemic, U.S. employers have consistently added jobs, resulting in an unemployment rate around 4 percent. Similarly, the Netherlands and Germany report low unemployment rates of approximately 3 percent, indicating that those without jobs are either transitioning between positions or entering the job market for the first time. Additionally, there are other contributing factors; in the U.S., a growing number of individuals are failing to meet military recruitment standards due to issues related to fitness, mental health, or prior criminal records, which has led to a diminishing pool of potential recruits.

Experts believe that the primary reason for the decline in recruitment is the absence of a significant national security threat to the U.S. “We’re victims of our own success,” stated Kate Kuzminski, director of the military, veterans, and society program at the Center for a New American Security (CNAS), a think tank based in Washington. “The perception of an existential threat is not as pronounced as it once was, which is positive, but it presents challenges for recruitment efforts.”

The U.S. military fell short of its recruitment goal by over 41,000 individuals last year, resulting in the smallest active-duty force in more than 80 years. Similarly, the British Army has not met its recruitment targets annually since 2010. In Germany, the Bundeswehr saw a reduction of 1,500 personnel last year, despite an extensive recruitment campaign. Even Ukraine, which is not a NATO member, has lowered its conscription age from 27 to 25 to secure enough soldiers to defend against the Russian invasion.

In Russia, the conscription age has been modified, increasing the upper limit from 27 to 30. Additionally, the Kremlin has implemented measures to re-enlist former soldiers, including those who have been out of service for decades. “This means that retired generals, who may have been inactive for 30 years, are being called back into duty,” noted Kuzminski.

Within the U.S. Army, the challenges of attrition and fatigue are particularly pronounced in combat arms units, with a notably high suicide rate among tank crews from 2019 to 2021. Air defense personnel are also experiencing significant stress due to their extensive global responsibilities.

Consequently, both the U.S. and European nations are actively seeking new recruits. Several countries, including Estonia, Finland, Lithuania, and Norway, already implement conscription for varying durations. Latvia is reinstating conscription, while Sweden, which previously conscripted a significant portion of its population, is reviving its mobilization strategy and aims to double its conscript numbers by 2030. Poland is striving to expand its military, aiming for a 250,000-strong active-duty force and an additional 50,000 territorial defenders, all while maintaining a low unemployment rate of around 2 percent.

For many years, European military strategies have been predicated on the belief that conflicts would occur outside their borders, emphasizing the need for technologically advanced and agile forces. Discussions surrounding the potential reinstatement of mandatory military service have largely centered on its perceived benefits as a means of fostering unity, instilling civic responsibility, and enhancing the relationship between the military and the general populace.

Currently, the ongoing and severe territorial conflict between Ukraine and Russia has resulted in significant casualties. While advanced technology plays a crucial role in modern warfare, it cannot compensate for the sheer scale of the conflict, as both nations face challenges in mobilizing sufficient troops. Leaders from frontline European nations—including the prime ministers of Estonia and Sweden, the defense ministers of Denmark and Norway, and Poland’s chief of intelligence—have recently cautioned that NATO may soon be drawn into a conflict with Russia.

During last year’s NATO summit in Vilnius, Lithuania, member states agreed to a new force structure that aims to expand the alliance’s high-readiness forces to 300,000 troops, a substantial increase from the previous 40,000. Achieving this goal is already ambitious, but to enhance NATO’s capacity to respond swiftly to territorial threats and engage in a sustained conflict with Russian forces, member countries will need to significantly bolster their military reserves.

European nations that have eliminated or paused conscription often face challenges in both recruiting and retaining adequate military personnel. A case in point is Germany, where Chancellor Olaf Scholz’s initiative for a military “Zeitenwende,” or a shift in defense strategy, aims to increase the Bundeswehr to 203,000 service members by 2031. However, despite ongoing recruitment efforts, the size of the German armed forces decreased to approximately 181,500 in 2023, down from 183,050 in 2022.

Similarly, the British Army, which has engaged a private company for recruitment, continues to fall short of its recruitment goals. In candid public statements, U.S. Navy Secretary Carlos Del Toro recently encouraged the United Kingdom to reconsider the scale of its military forces. The United States is also experiencing recruitment difficulties across all branches of the military, raising concerns that the reliance on an all-volunteer force is widening the gap between the military and civilian populations.

A significant challenge facing military organizations is the retention of soldiers long enough to maintain a force that is both experienced and combat-ready. France is currently experiencing difficulties in retaining its personnel, with uniformed members now serving an average of one year less than in previous years.

In 2022, the rate of early contract terminations reached 32 percent, while the military’s goal is to keep this figure around 25 percent. The French director of human resources for the Ministry of Armed Forces informed parliament in 2023 that, although some turnover is expected, the scale of this issue is unprecedented. In Poland, the government has introduced a voluntary one-year basic military service to bolster recruitment and enhance its reserve forces.

The aim is to establish NATO’s largest land army, increasing the number of professional soldiers in the Armed Forces to 250,000 by 2030 and eventually to 300,000, including reserves, by 2035. However, critics argue that these ambitions are unrealistic, citing retention issues and a record number of experienced personnel leaving the military. Despite acquiring new tanks for heavy divisions, Poland is facing a shortage of troops to operate them. While the number of recruits in 2022 increased, nearly 9,000 seasoned soldiers exited the armed forces, leading to a significant loss of expertise.

The transition from conscripted to all-volunteer forces has rendered many European militaries vulnerable, as they struggle to meet recruitment goals and lack the necessary manpower to defend against a more aggressive Russia. In response, these nations are exploring various strategies to bolster their diminishing forces, including the potential reintroduction of conscription. They are observing neighboring countries to the north and east, which have either maintained or recently reinstated conscription systems, each with its own distinct characteristics.