Partly in response to Finland and Sweden joining NATO, the alliance plans to triple the size of its battlegroups, taking them from battalions to brigades.
NATO will soon increase the size of its Response Force, a multinational package of air, land, and sea forces meant to come to the aid of frontline states. In the wake of Russia’s ongoing invasion of Ukraine, the move will boost the force from 40,000 to “well over” 300,000, marking the largest assemblage of NATO military forces since the end of the Cold War.
Speaking at a NATO conference in Madrid on June 27, NATO Secretary General Jens Stoltenberg announced the expansion. “We will enhance our battlegroups in the eastern part of the Alliance up to brigade-levels. We will transform the NATO Response Force … And increase the number of our high readiness forces … to well over 300,000.”
“NATO established its high-readiness response force (the NRF) in 2002 and bolstered it in 2014 following Russia’s annexation of Crimea,” Sean Monaghan, a visiting fellow at the Center for Strategic and International Studies (CSIS), explains to Popular Mechanics. “It was deployed for the first time in a collective defense and deterrence role following Russia’s full-scale invasion of Ukraine in February.
In 2017, NATO deployed four battalion-sized battlegroups in frontline states including Estonia, Latvia, Lithuania, and Poland—states bordering, or in the vicinity of, Russia. NATO doubled this commitment after Russia invaded Ukraine. “The NRF was activated following Russia’s invasion in February,” Monaghan explains, “with 500 French lead-element troops deploying to Romania and other nations including the U.K., U.S., and Germany sending forces to bolster NATO’s presence in its member states in eastern Europe.”
In total, the NRF surged four more battlegroups into Bulgaria, Hungary, Romania, and Slovakia, for a total of eight deployed across Europe. Each battalion consists of 800 to 4,000 military personnel, with supporting tanks, infantry fighting vehicles, artillery, and helicopters. Each battle group is on average one-third the size of a Russian brigade tactical group, the basic unit of action for the Russian Ground Forces. Russia deployed 110 brigade tactical groups in the invasion of Ukraine.
The NATO reaction force trains constantly to achieve a high level of readiness. The most recent exercise, Monaghan explains, was exercise Cold Response 2022, which took place in Norway and involved 30,000 troops from 27 member countries.
The invasion of Ukraine and NATO’s imminent expansion to include Sweden and Finland increases both the area that the alliance must protect and the tension for existing members neighboring Russia. Sweden and Russia are adjacent to the Baltic Sea. Sweden’s coastline, including the island of Gotland, is vulnerable to Russian naval action, from a blockade to amphibious invasion. Finland’s situation is even more precarious due to its 832-mile-long land border with Russia. Russia invaded Finland in 1940, killing over 19,000 Finns and forcing the country to cede 11 percent of its territory to Moscow.
Meanwhile, Latvia, Lithuania, and Estonia are warning they need NATO forces stationed in their territories to avoid Russian aggression. All three of the Baltic states are relatively small and could quickly find themselves under major Russian attack. Estonia’s prime minister, Kaja Kallas, warned this week that without more NATO troops based in her country, the capital of Tallinn could be quickly “wiped off the map.”
Stoltenberg’s comments indicate that the alliance plans to triple the size of the NATO battlegroups, from battalion to brigade size. A NATO brigade would be substantially more capable of resisting a Russian invasion, though it would still find itself outnumbered. The goal would be to hold on until more NATO forces, drawn from the alliance’s Follow-On Forces Group, arrived to help turn the tide.
A multinational approach to defense is great when it works, but there are disadvantages, Monaghan explains. “Deploying the NRF requires a consensus among allies—this is one of the reasons it has not been used until now. It also means NATO’s deterrence depends on the threat of deploying forces quickly to any crises, and keeping forces at high readiness is costly.”
Monaghan believes that NATO “will likely change its deterrence model in Madrid from ‘deterrence by reinforcement’ to more forward-positioned forces, which can form a ‘forward defense.’” In the former, the alliance would station forces in their home countries, with the promise that they would quickly deploy in a crisis. “Forward defense,” on the other hand, would station larger forces in potential crisis areas to deter, and if necessary resist, attack from the outset.
In addition to the NRF, there are other mechanisms to reinforce NATO member states. The United Kingdom leads the Joint Expeditionary Force, or JEF, consisting of the U.K., Norway, Sweden, Finland, Denmark, the Netherlands, Iceland, and the Baltic States. The United States could also take independent action, moving ships, planes, and ground troops to the Atlantic or bases in Europe in a crisis.