The Kyiv Independent’s Martin Fornusek interviewed Phillips O’Brien, a U.S. historian and professor of strategic studies, about Ukraine’s decision to stop trying to win over President Donald Trump and the broader shift in Kyiv’s wartime strategy.
The exchange pointed to a turning point in the politics of the war, as Kyiv concluded that appeals to personal favor, transactional concessions, and symbolic gestures could not overcome a deeper realignment in Trump’s approach to Russia’s brutal war.
The earlier strategy had followed the logic of dependency. Since Russia’s full-scale invasion in 2022, Ukraine had relied heavily on the United States for military assistance, air defense systems, intelligence cooperation, and diplomatic support. That dependency gave Washington enormous influence over Kyiv’s choices, especially as Ukraine tried to preserve bipartisan support and avoid becoming trapped inside U.S. domestic politics.
Under Trump, who campaigned under the false claim that he would end the war within the first 24 hours of his re-election, that calculation changed.
Ukraine’s leadership had initially sought ways to keep the United States engaged, including gestures meant to satisfy Trump’s shallow ego and his preference for transactional politics. The effort, however, collided with a toxic policy environment. It treated Ukraine not as an ally defending its sovereignty, but as a subordinate to be pressured into concessions so that Trump could enrich his friendship with Putin.
The result was a recognition in Kyiv that persuasion had limits. The problem was not only a difficult president or an unstable alliance. It was the discovery that a state fighting for survival could not build its war strategy around the hope that personal diplomacy would restore a security relationship that had already been weakened.
That shift mattered because American power had long functioned as both shield and constraint. For decades, the post-1945 U.S.-led security order rested on the assumption that Washington’s commitments, while sometimes uneven, provided the foundation for European defense.
Ukraine’s war exposed the fragility of that assumption. It also showed the risks faced by countries whose survival depends on a patron whose political leadership can change direction.
The break with Trump therefore became part of a broader transformation in Ukraine’s wartime identity. Ukraine had to move from seeking reassurance to building leverage. It had to treat American support as uncertain rather than guaranteed, and it had to prove that its resistance could continue even when the United States became less reliable.
That transformation was not only diplomatic. It was also military and social. A country under invasion had to expand its own capacity, sustain morale, absorb losses, innovate under pressure and deepen cooperation with European partners. The more Ukraine showed it could fight without full U.S. backing, the less Washington’s pressure could define the limits of Ukrainian strategy.
The politics of aid became central to this new phase. Partial support from Washington preserved influence without restoring trust. Continued intelligence cooperation and some previously approved weapons under President Joe Biden’s administration gave the United States leverage. But the reduction of new assistance forced Ukraine to adapt to scarcity.
In that environment, aid was no longer simply a measure of alliance solidarity. It became a mechanism through which Washington could attempt to shape negotiations, battlefield expectations, and Kyiv’s room for maneuver.
Ukraine’s battlefield adaptation gave that political shift substance. As U.S. support became less dependable, Ukraine placed greater emphasis on domestic production, tactical innovation, and the ability to impose costs on Russia beyond the front line. The significance was not limited to equipment. It changed the political psychology of the war by showing that Ukraine’s survival was not reducible to the decisions of a single foreign capital.
That evolution gave Kyiv more freedom to reject pressure for a settlement built around territorial loss or Russian advantage. A country that can continue degrading an invading army is harder to force into accepting terms framed by someone like Trump as practical or inevitable. Ukraine’s military resilience therefore became a form of political independence.
Europe’s response added another layer to that transformation, though not a uniform one. The weakening of trust in Washington pushed many European governments to reconsider assumptions that had shaped the continent’s defense policy since the Cold War. The old arrangement, in which the United States carried the central burden of deterrence while many European states deferred difficult spending decisions, became less tenable.
The shift has been clearest among countries closest to Russia. Poland, the Baltic states, the Nordic countries and, increasingly, Germany have moved with greater urgency because geography has imposed a sharper sense of risk. Farther from Russia, some governments have remained slower to convert concern into sustained military investment. That division shows that Europe is not a single strategic actor. It is a continent whose threat perception is uneven, shaped by history, borders, and domestic politics.
Still, the direction of travel is important. Even a divided Europe has begun adjusting to a world in which U.S. support may no longer be automatic or dependable. That adjustment does not require hostility toward the United States. It requires a more mature security relationship, one in which European defense is not held hostage to the political volatility of Washington under Trump.
Russia’s position, meanwhile, remains dangerous but strained. The Kremlin has shown that authoritarian systems can absorb enormous human and economic costs, suppress dissent, and continue a war long after outside observers expect exhaustion. But endurance is not the same as strength. Attrition, inflationary pressure, depleted reserves, and limited production capacity can restrict Russia’s ability to improve its battlefield position, even if they do not produce immediate political collapse.
That distinction matters. Predictions of sudden Russian collapse have repeatedly encouraged unrealistic expectations. A more sober assessment is that Ukraine’s best path lies in sustained degradation of Russian military capability. The goal is not to wait for a dramatic internal rupture in Moscow, but to make continued aggression more costly, less productive, and harder to sustain.
The war’s end may therefore depend less on a single diplomatic breakthrough than on the cumulative pressure created by Ukraine’s adaptation, Europe’s rearmament, and Putin’s mounting constraints. The emerging security map is one in which Ukraine can no longer rely on American consistency, Europe can no longer outsource its defense, and Russia can no longer assume that time alone guarantees advantage.
For Ukraine, that map is harsh but clarifying. The failure of persuasion with Trump did not end the struggle. It forced Kyiv to define survival through autonomy, endurance, and the steady construction of strategic leverage.
