As the last of the snow thawed around Helsinki in March 2026, the leaders of the Joint Expeditionary Force (JEF) met to discuss the future of European security. Their joint statement of 26 March reaffirmed the group’s Enhanced Partnership with Ukraine and their eagerness to learn from the country’s experiences on the battlefield.

Despite being lead from London, the JEF remains largely unknown in the UK. This is a shame, as it represents one of the British military’s few successes in the last decade. Founded in 2014, the JEF has grown to encompass all the Scandinavian and Baltic states, alongside the Netherlands and the UK. Since 2024, it has focused on two priorities: protecting Northern Europe; and developing combat groups able to respond rapidly to Russian aggression which falls below the threshold of collective defence under NATO’s Article 5.

The JEF has become increasingly essential as an organisation for several reasons. First, Russian sabotage missions in Europe have increased this decade, especially in the Baltic. Russia’s navy and shadow fleet have also become increasingly brazen, repeatedly entering British, Dutch and Norwegian territorial waters.

Second, for Britain and nearly all of the JEF members, chronic underinvestment in their armed forces has meant that acting alone is now practically impossible. Despite the threat level, Starmer’s Government continued to cash in on the peace dividend. As a result, Britain now has its smallest standing army since 1823 and a Royal Navy unable to put more than a dozen frigates and destroyers to sea at short notice. As John Healey said in his resignation letter, the Government’s current spending plans will “reduce the readiness of our Forces, increase the risk to personnel on operations, and could make the country less safe.” For Britain, therefore, joint operations are no longer optional; they are an absolute necessity.

Finally, the United States appears serious about decreasing its military presence in Europe. Although presidents as far back as Eisenhower have complained that the Europeans were “making a sucker out of Uncle Sam,” President Trump has been blunt about the need for the US to leave Europe’s defence to Europeans. As his administration’s 2025 National Security Strategy outlines, the US desires that the Europeans “take primary responsibility” for their own defence. Although the number of US troops stationed in Europe rose to around 100,000 by 2024 in response to Russia’s invasion, Trump has wound this number down to around 70,000 today. Over the next decade, this number is likely to fall further as the US shifts resources to the Indo-Pacific. Britain, whether it is ready or not, will be expected by its allies to help fill the vacuum in manpower and leadership.

This brings us back to the Ukraine. While peace talks are currently on ice, the war’s decent into stalemate means both sides are in the position to discuss terms. The West has already begun considering how best to assist Ukraine after the war, including rebuilding its civilian and military infrastructure. Of course, the EU and NATO can, and will, provide assistance. However, since Ukraine will likely be prohibited from becoming full members of either organisation, hands-on assistance will have to be found elsewhere.

A coalition of the willing may have a place, but, based off the current commitments made by its members, it will not be enough. As with much of the West’s approach to this war, the coalition’s leaders have been effusive in their praise for Ukraine but sheepish when it comes to providing the best hardware or about what concessions Ukraine may have to make to secure peace. The coalition’s proposed peacekeeping force in particular risks becoming an exercise in wishful thinking. When one considers that the UK would struggle to send and maintain a full brigade’s worth of soldiers, it is highly unlikely that the coalition will be able to muster the 100,000 troops required to defend Ukraine’s likely frontiers.

The JEF offers a much more realistic route for the UK to meaningfully contribute to Ukraine’s long-term security. Its model as a rapid reaction force is well suited to the country’s most pressing defensive challenge, namely the ability to respond swiftly to Russian provocations before they can escalate into a full-scale invasion. Equally, JEF member states have consistently been among the most hawkish voices on Russia. Polling data speaks to their support for Ukraine, with an average of 80% of Swedes, Danes, Finns, Lithuanians, Latvians and Estonians supporting their governments’ financial and military packages to Ukraine.

In practical terms, there are two areas where the JEF could utilise its existing skillset and equipment. It could establish a drone surveillance network along Ukraine’s northern border, and it could develop drone-based riverine defences along the Dnieper and Dniester, utilising JEF-trained units embedded within the Ukrainian army.

A permanent fleet of drones operating non-stop in the Chernihiv Oblast would allow the Ukrainians to monitor the region’s frontier while providing them and the JEF nations with advanced warning of any Russian military build-up. This would extend the JEF’s philosophy of rapid reaction and early warning beyond its borders while giving Ukraine a credible tripwire capability.

Protecting the Dnieper and Dniester would be a greater challenge, but one that JEF members are well placed to meet given their experience in maritime and littoral operations. Both rivers represent critical strategic boundaries, with the Dnieper bisecting the country and the Dniester marking its southwestern edge; losing total control of either would likely lead to Ukraine’s total collapse. As with the northern frontier, unmanned UAVs could provide continuous surveillance along key stretches, while JEF-trained riverine units equipped with drone-launched munitions and rapid-deployment craft could react to any attempted crossing. Both schemes would help Ukraine build up multiple layers of high-tech defence which Russia would find difficult to overwhelm.

For nearly five years, Ukraine has suffered from a surplus of Western sympathy and a shortage of Western resolve. If the UK and Europe are serious about securing the peace, they must move beyond declarations and plan defences capable of deterring and, ideally, defeating future Russian aggression. The JEF is not a silver bullet, nor do I suggest it can carry the burden alone. But, as the United States turns its attention elsewhere, it offers Britain a practical means of strengthening European security while helping to ensure that any peace in Ukraine is properly defended: not merely declared.

The original photo is of a Finnish tank crew member manning a Leopard 2A4. Taken by 1st Sgt. Austin Berner of the US Army Reserve.