The Democrats scored a landslide victory in the 2026 midterm elections. The Republican Party has badly lost Senate seats and governorships across the South, the Midwest and the West, including in traditional strongholds like Texas. What this all means is a major political debacle for the Trump administration. The president will have to deal with a Democratic-controlled Congress opposing most of his policies – including in the foreign and defense fields. In the short term, this new political balance in Washington will likely have a limited impact on Euro-Atlantic security, also concerning Russia and Ukraine, in combination with long-term trends shaping NATO evolution and US role within the alliance.
Such impact may probably regard mainly three elements: the American military presence in European allies; the US stance on the Russia-Ukraine war; and the security implications for Europe of the conflict with Iran.
A slower reduction of the American military presence in Europe?
The Trump administration had initiated a partial and gradual drawdown of military capabilities from Europe, within an overall force posture review. This was not meant to be a US exit from NATO, nor a complete withdrawal of American forces from the Old Continent, but it surely set a path towards a significant reduction — both qualitative and quantitative — in terms of military equipment and personnel. A path marked by uncertainties, administration criticism against Europe, and tense relations among allies. Indeed, this drawdown has been the subject of heated negotiations within the Alliance, concerning collective deterrence and the defense posture, regional plans, NATO force model and defense planning process. European nations have to fill the gaps left by the Americans if they want to maintain the same level of conventional deterrence against Russia, as well as the ability to defend allied territories should Moscow directly test NATO resolve.
The more drastic and immediate the reduction of American military presence, the harder it becomes for the Europeans to fill these gaps, thus creating a window of opportunity for an aggressive and opportunistic Russia keen to take escalatory risks.
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With a US Congress now controlled by the Democrats, there will likely be more pressure on the Trump administration for a limited and gradual drawdown. Previous lawmakers already passed a law to constraint the White House’s ability to reduce the US military presence in Europe below a certain threshold, but Trump has so far been keen to ignore or circumvent legal and institutional barriers to his actions. A more robust opposition by the Congress, coupled with Trump’s decreasing grip on the Republican party after such an electoral defeat, could result in further constraints on the reduction of the American military presence in Europe. Moreover, possible turnovers within the administration, including with regards to Pete Hegseth, may weaken top-down grip on the Pentagon and State Department offices in charge of managing the negotiations within NATO, the finalization of the force posture review, and their implementation.
These developments would make the ongoing burden-shifting from US to Europe and Canada more balanced, predictable, effective and sustainable, and thus strengthen NATO’s overall deterrence and defense posture, to the benefit of the security of the whole Euro-Atlantic region.
More of the same on the Russia-Ukraine war
The extent of the Republicans’ defeat, rapidly acknowledged by both Trump and Vice-president Vance, paves the way for different scenarios concerning the White House approach to the Russia-Ukraine conflict. Some observers argue that Trump will focus more on foreign policy – an area where the Congress has less leverage to constrain the president compared to domestic ones – in an effort to secure a political legacy and leave his mark on history, as many other US presidents tried to do in their last years of mandate. Others warn that Trump may become even more unpredictable, as he will have to contend with a combative Democratic-led Congress. There are also concerns that the White House might push even harder to normalize relations with Russia at the expense of Ukraine, in a bid to curb energy-related inflation which was a primary factor in the GOP’s electoral defeat. While several scenarios are possible, for the next two years a couple of elements will likely mark the administration stance on Russia-Ukraine war: the limits of US power and the Trump administration’s ineffectiveness.
The limits of America’s ability to influence the Russia-Ukraine conflict have become evident. Trump made a genuine diplomatic attempt to convince Putin to strike a peace deal by satisfying many of his requests and rolling out the red carpet in Anchorage in August 2025. At the same time, the White House intermittently attempted to force Zelensky to accept hard peace terms, halted the military supplies guaranteed by the previous administration and repeatedly interrupted intelligence sharing with Kijev. Despite all these efforts made during the administration’s first two years, when Republicans controlled both the House and the Senate and Trump enjoyed strong political momentum, the outcome of the US mediation has been almost zero. The Kremlin’s unwavering stance on requests largely unacceptable for both Ukraine and the US has been the main obstacle to peace negotiations, and will remain so. The fade of next peace talks is likely to be shaped more by the balance of power between Russia and Ukraine – provided Europe continues to support the latter – than by US pressure.
The results of the midterm elections enhance these limits. For example, any further attempt to achieve a rapprochement with Russia or to put under pressure Ukraine for hard concessions would now run up against constraints and opposition from the Congress — obstacles the president did not face previously. Furthermore, because of the electoral defeat Trump now has less political capital to spend on this policy item, and he faces a political time horizon of only 15 months, as the American election campaign will be in full swing again by the spring of 2027 and he has no chance to pretend to run for a third mandate.
The flip side of these limits is the Trump administration’s ineffectiveness as a mediator between Russia and Ukraine. The lack of consistent direction, its tendency for frequent changes of rhetoric and actions, the ruptures brought in the Western camp, the impulsive, highly personalized decision-making, altogether made the US approach rather ineffective and inefficient. This is not to say Trump had no vision on the conflict. The idea of normalizing relations with Russia even to the detriment of Ukraine territorial integrity, sovereignty and security has been the Northern Star of his approach to this “mediation”. However, such overarching goal did not translate into an articulated, consistent and feasible strategy to reach it. As he enters the lame duck phase of a second term with a Democratic-controlled Congress, the inconsistency and ineffectiveness of the administration’s approach will be amplified by the constant attrition with Capitol Hill and a weakening Republican support for the president’s leadership. The most likely scenario is therefore a stalemate of peace negotiations and the continuation of the war at least for the next few years – that is, more of the same.
Stuck in the Iranian cul de sac
Limitations to US leverage and ineffectiveness have characterized also the ill-designed military campaign against Iran going on since February 2026. After the first tactical successes, none of the different goals stated over time by the Trump administration has been achieved, while as a result of American actions Iran currently controls (or at a minimum exercise a degree of influence over) the Strait of Hormuz more than before the start of the conflict. A further escalation by the American side — whether through a ground invasion or the use of nuclear weapons — faced deep-rooted domestic redlines before the midterms, and has become even less likely now that the electorate has punished such disastrous interventionism – also in terms of US inflation – by handing control of the Congress to the Democrats.
It is difficult to foresee whether a lame duck Trump might be more aggressive or more conciliatory toward the Iran leadership, given that he has no other election to lose. In any case, an intensification of an air campaign will be limited in scope and duration by the dire status of Pentagon’s stockpiles and by insufficient production capacity of the US industrial base, while facing the resilience of the Iranian regime. Accordingly, such an approach is unlikely to win the war. On the contrary, another US-Iran truce is possible, but it is equally possible that such an agreement could be rapidly broken by either side, as occurred in Summer 2026. Moreover, differences may emerge within the administration on the best course of action, as in the immediate aftermath of the midterm elections Vance begun to publicly question whether or not nine months of conflict have been the right choice considering its economic and political costs.
Again, the more likely scenario is a continuation of no war-no deal current situation, with the Trump administration stuck in the Iranian cul de sac it has created. This in turn would fuel regional instability and insecurity as well as negative consequences on Europe’s sea lanes of communication, supply chains and energy prices. Such a scenario is relevant for NATO too, as the divergences between the White House and the rest of allies on the war against Iran spilled over on the use of US military bases in Europe, military aircraft’s access to European air spaces, and Trump’s harsh criticism of the European allies and even of NATO as such because of the lack of support for his adventure in this cul de sac. The Europeans will have to work to decouple NATO, and above all the collective deterrence and defence of Euro-Atlantic region, from the war in Iran and the related transatlantic divergences.
NATO’s long-term trends
The midterms’ impact regards not only the US military presence in Europe and its stance on the Russia-Ukraine war and the conflict against Iran. The November 2026 vote marks the beginning of the end of the Trump presidency, is set to fuel an internal debate within the Republican Party regarding its post-Trump identity and vision, and gives the Democrats a good chance to win the next presidential elections. However, certain long-term trends concerning the evolution of NATO and the US role within the Alliance began well before Trump’s presidency, were accelerated and intensified by the current administration and will continue even if a Democrat or a post-Trump Republican will enter the White House. Three of these trends are particularly relevant and challenging for NATO allies: the reduction in the American military presence in Europe; the need for Europeans to increase their defence spending; a US reassessment of Europe’s importance for its national security.
The downsizing of US capabilities in Europe has continued through the entire post-Cold War period, it was halted and partially reversed after the Russian invasion of Ukraine, and then it re-started and accelerated under the Trump administration. Against this backdrop, a more pro-Europe Democratic president would not significantly increase this military presence once again. He or she might temporarily suspend the drawdown, and/or ensure that any further reduction is partial, gradual, coordinated, predictable and smooth. Yet an undeniable, long-term trend is that Europeans will have to shoulder a greater burden and risk for the collective deterrence against Russia and for the defence of their own continent, with a smaller US footprint and support than in the previous eight decades. Whether under a Democratic or Republican administration, the US are set to push for a “burden shifting” – no a “burden sharing” – and for a NATO 3.0 that refocuses on the Euro-Atlantic area but with Europeans at the forefront of collective deterrence and defence in terms of both contributions and risks.
The second, related, long-term trend concerns the need for European allies to increase military spending and the US pressure to do so. The goal of 2% GDP on defence was established in 2014 by NATO heads of state and government during the Obama administration. This objective has been pursued by both successors (Trump and Biden) —albeit with varying degrees of intensity and different tones — up to the 2025 summit in the Hague, when NATO nations raised the bar to 3.5% GDP by 2035 for core defence spending.
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In Italy and elsewhere in Europe, some policymakers might wrongly assume that with Trump and Trumpism past their political peak, the related threats and hardship will also disappear, the allies will return to more reasonable negotiations on defence budgets where Western and Southern European governments can kick the can down the road when it comes to military spending. This wishful thinking is likely to be frustrated by the fact that no future US president would lower or postpone the target of 3.5% GDP on defence by 2035. The perception that Europeans are free riders vis-a-vis the US security umbrella funded by American taxpayers is deeply entrenched in the United States’ electorate, public opinion and establishment, it cuts across the political spectrum and spans the entire country from coast to coast. This will continue to influence any US administration’s approach towards its allies. American pressure to persuade the Europeans to spend more for Euro-Atlantic security to spare US resources is set to continue because of several factors: American sovereign debt now hovers beyond 125% of GDP and is likely to grow even further; the military capabilities are overstretched by the long-term confrontation with China and the recurrent conflicts in the Middle East, and any further increase of the Pentagon’s budget are and will be under political scrutiny; demographic trends gradually reduce the portion of electorate somehow personally connected with Europe by changing the priority of this region in the domestic political debate.
All these factors concur to another related trend: a reassessment of Europe’s importance for US national security. The collective societal experience of the 20th century led most Europeans and many Americans to believe that the security of Europe and North America is inseparable. Two World Wars and 45 years of Cold War shaped the memory and mindset of four generations of ruling classes. But these generations are inevitably exiting the US establishment, including in the Democratic Party. Newly elected senators and governors such as El-Sayed, Ossoff and Talarico were born in the 1980s and have no meaningful memory of the Cold War and of the related US role in Europe. And because of the ongoing demographic changes, some of the new leaders do not even have shared memories transmitted by their parents. Against this backdrop, the 2025 National Security Strategy prioritized first the Western Hemisphere, second the Indo-Pacific, third the Middle East and lastly Europe. Such prioritization does not come only from Trump or the MAGA constituency. Among current and upcoming Republican or Democratic leadership it is hard to find the political appetite to let Kyiv join NATO or to participate in the European-led multinational force to be deployed in Ukraine after an eventual peace deal.
Such reassessment underpins both the abovementioned reduction of the American military presence in Europe and the pressure on NATO allies to invest their own budgets to deter Russia and defend itself from this European neighbour. But it goes beyond that and the burden-shifting among allies towards a NATO 3.0. There is a growing plurality of views across the American political spectrum regarding the relevance of European security to US national interests. Among both Democrats and Republicans, emerging leaders may well decide that it is more advantageous for the US to normalize relations with Moscow by sacrificing Ukraine and by leaving the European allies to deal with the risks resulting from an emboldened Russia. This decision could be driven by a will to focus American resources to compete with and contain China, and possibly to weaken the Moscow-Beijing partnership by pleasing Russia on Ukraine, or simply by the belief that the protection of US national security begins at the borders with Mexico and not at the Estonian ones with the Russian Federation.
To conclude, the short-term impact of the midterms is likely to benefit NATO and transatlantic relations in a limited albeit significant way. The new political landscape in Washington opens different scenarios about the US approach to Europe, the Russia-Ukraine war and the conflicts in the Middle East. Yet there are long term trends influencing and challenging both NATO and transatlantic relations, which interplay with the midterms’ impact and contribute to shape the different scenarios. All in all, a stronger European pillar within NATO seems to be the only way to keep the transatlantic alliance sufficiently balanced, sustainable and robust through different political cycles by coping with the evolving US role in the Euro-Atlantic region.