Nuclear tensions in Europe have intensified considerably since Russia annexed Crimea in 2014 and invaded Ukraine in 2022, with changes in rhetoric, operations, and infrastructure around nuclear weapons, according to research from ten sources. Russia has fielded new nonstrategic nuclear weapons systems, increased military exercises, issued nuclear threats, and upgraded its doctrine to potentially lower its nuclear threshold. NATO is responding by modernizing its nuclear forces, increasing strategic bomber operations and nonstrategic nuclear posture, changing submarine operations, and talking more openly about nuclear weapons. Nine countries currently operate nuclear forces in Europe: Belarus, Belgium, Germany, France, Italy, Netherlands, Russia, the United States, and the United Kingdom, with the UK announcing plans to acquire nonstrategic nuclear weapons. Russian officials have issued a wide range of nuclear threats since shortly before the 2022 invasion, with nonstrategic nuclear weapons potentially used first, while major media reports indicate Britain and the US have ramped up drills to counter a potential Russian nuclear strike from space. America's top military space commander warned the US must change its approach to prevail in future conflicts, which major media suggests could be waged outside Earth's atmosphere.
Russian aggression extends beyond Ukraine, with a strategic objective of undermining stability in the Euro-Atlantic region to reverse its loss of status after the Cold War, demonstrated by hostility and hybrid attacks, according to research from ten sources. This includes drone incursions, cutting undersea cables, and targeting space assets, which could spiral into open conflict. Russia has used chemical weapons in Ukraine, specifically chloropicrin, and on European streets, described as the most acute nuclear, biological, and chemical threat in the near-term in US strategy documents. NATO Secretary General Mark Rutte warned in December 2025 that the alliance should prepare for a Russian attack within five years. The UK, as a founding member of NATO and a champion of collective security, views strength as the only effective response to tyrants like Vladimir Putin, with national security being the first responsibility of any government in a world changed by Russian aggression, strategic competition, extremist ideologies, and hostile state activity on British soil.
On the battlefield, Russian forces conducted five platoon- to battalion-sized mechanized assaults in western Donetsk Oblast on July 29 and 30, 2024, as part of a forecasted summer offensive. They marginally advanced on the southwestern outskirts of Kostyantynivka during a reinforced-battalion sized mechanized assault on July 29, 2024. Ukrainian forces struck eight tanks, 12 armored fighting vehicles, nine motorcycles, and a buggy during that assault near Kostyantynivka. Vladimir Putin invaded Ukraine in 2022 after years of tension, amassing troops and making demands rejected by the West, with stated reasons including false claims of genocide against Russian speakers. Russia still occupies roughly 20 percent of Ukraine after gaining almost five thousand square kilometers of territory in 2025, with continued bombardment and drone attacks.
The human cost of the war is staggering, with Ukrainian President Volodymyr Zelensky stating in December 2024 that 43,000 Ukrainian soldiers had been killed and 370,000 injured, and 198,000 Russian soldiers killed and 550,000 injured, though these claims are unverifiable. In June 2025, CSIS estimated Russian military casualties would reach one million during summer 2025, and Ukrainian casualties since 2022 to be 400,000, including 60,000–100,000 killed. A January 2026 UN report found nearly 15,000 civilians killed and more than 40,600 injured since February 2022, with the majority in Ukraine. Fighting and air strikes have inflicted nearly 56,000 civilian casualties, with 3.7 million internally displaced, 5.9 million refugees, and 10.8 million needing humanitarian assistance.
International aid has been substantial, with Ukraine receiving about $188 billion in aid from the US and $197 billion from the EU since January 2022. Diplomatic efforts include the Trump administration pledging to seek a settlement to end the war with a twenty-point draft peace deal, but terms remain unclear and Russia insists on adherence to Putin's summit with Trump.
Rhetoric between Russia and Western allies has escalated sharply, with the Russian defence ministry accusing the UK of provoking Ukraine into attacking Russian territory and threatening to hit decision-making centres in Kyiv, possibly regardless of Western advisers present. UK defence minister James Heappey said it was not necessarily a problem for Ukraine to use UK-supplied arms against military targets in Russia, calling strikes on supply lines legitimate. Foreign minister Sergei Lavrov accused NATO of conducting a proxy war and warned Western weapons in Ukraine would be fair targets, repeating warnings of a third world war.
Criticism of UK defense preparedness has mounted, with George Robertson, a former NATO chief and UK defence minister, accusing Prime Minister Keir Starmer of corrosive complacency and unwillingness to invest in defense, putting the UK in peril. Robertson, Gen. Richard Barrons, and Fiona Hill conducted a strategic review finding decades of cuts left the UK dangerously unprepared for conflict, recommending resilience, armed forces buildup, and investment. Gen. Richard Barrons said at the current pace, it would take the UK about 10 years to be ready for war, but allies suggest 3-5 years given Russian preparations for conflict with Europe. Former US President Donald Trump criticized Keir Starmer for being weak on defense, saying he is not Winston Churchill.
The UK government has agreed with the assessment but has postponed a concrete funding plan multiple times, with a Downing Street spokesperson citing the largest sustained defense spending increase since the Cold War. The UK could become embroiled in a peer conflict in the near future, with adversarial nations like China, Russia, Iran, and North Korea posing a growing threat.
In response, the UK's strategic defense approach emphasizes that foreign policy should answer directly to the concerns of working people, as wars drive up bills, cyber-attacks undermine public services, and criminals smuggle illegal migrants. Collective security led by NATO remains the cornerstone of the UK's strategy, but sovereign strengths must be increased, requiring mobilizing every element of society towards a collective national effort. The UK must increase national warfighting readiness urgently, according to the Strategic Defence Review.
Several key unknowns persist in the conflict. What specific changes the US must make to prevail in future space conflicts, as warned by America's top military space commander, remains unclear. The exact terms of the proposed peace deal to end the war are unknown. Whether Russia will escalate its threats further is unknown. The verifiable casualty figures for Ukrainian and Russian soldiers in the war are also unknown, given conflicting and unverified claims from various sources. How the UK plans to acquire nonstrategic nuclear weapons as announced, including timeline and capabilities, is unknown.