After Donald Trump decided to stop military support for Ukraine, a frequently asked question was how long this country will resist Russian aggression under the new conditions.
The answer is difficult to give because it depends on dozens of political, military, and economic unknowns.
Let’s remember that three years ago, when Vladimir Putin decided to invade Ukraine, even the most optimistic military experts were saying that Kiev’s forces would collapse within a maximum of three months.
Dozens of studies were written comparing data on the "great Russian army" and Ukraine's weak military equipment. And what happened? Kiev continues to resist today, causing a huge strategic surprise and fundamentally changing the way modern wars are fought.
Indeed, the cessation of American support is a significant event. The defense of cities and critical infrastructure depends on Patriot systems. The lack of projectiles for these systems will once again open the way for Russian missiles towards Kiev and other major cities.
The basic scenario is to maintain positions and create conditions for proper diplomacy to end this war as quickly as possible with a just peace. We need peace, a true and honest peace - not endless war. And security guarantees are essential.
Volodymyr Zelensky, President of Ukraine, March 4, 2025
There are discussions to replace them with NASAMS, a similar defensive system, created through Norwegian-American collaboration.
The problem is that the projectiles for this system are produced by a US company, and Trump's imposed ban could severely affect Ukraine's anti-aircraft defense.
Currently, in the neighboring country, there are five operational Patriot batteries and 12 NASAMS.
Another issue is related to motorized armored vehicles; American ones are extremely high-performing, resistant, and easy to maintain, while those produced by EU states are different models, with different characteristics, harder to maintain, and in insufficient quantities.
At this moment, we produce a third of the weapons we need. Our goal is to reach 50%.
Denys Shmyhal, Prime Minister of Ukraine
Moreover, there is another crucial area where the US played a major role, that of military intelligence provided to Ukraine. It is unknown whether this support has also been halted by the White House order or if it continues, even in a masked form or through intermediaries.
The democracy in the US has many layers, and it is difficult, just 6 weeks after the new administration took office, to understand what is happening in agencies like the CIA and FBI, whose leaderships have been changed and replaced with ones loyal to Donald Trump.
These critical institutions for the American state, including the Pentagon, have numerous layers of command, control, and communication, and the way they react involves a certain inertia if not a reshaping of decisions coming from political leaders.
Ukraine Can Resist Until the End of the Year
When it comes to the front line, "Ukraine's current approach to defensive operations combines mines, attack drones, and classic artillery salvos to keep Russian forces at a distance of up to 30 kilometers. Most of the casualties among Russian forces are now caused by mines and drones produced in Ukraine," explains Michael Kofman, military expert at the Carnegie Endowment.
"Traditional artillery strikes are less relevant at this moment, with a relative parity between the two sides. Relying on projectiles delivered recently by the US in the past months, which have anticipated deliveries, Europeans could support Ukraine until the end of this year," added Michael Kofman.
The main effect of stopping military aid to Kiev is that peace negotiations have been compromised, with Donald Trump indirectly acknowledging that he has no leverage or does not want to use any political leverage over Vladimir Putin.
The suspension of American assistance to Ukraine is an unfortunate and significant development, but it may not have an immediate impact. Ukraine is much less dependent on the US for daily battlefield needs in 2025 than it was in previous periods of the war.
Michael Kofman, military expert
Also, very little is known about Russia. Signals from the Kremlin are ambiguous and have not supported Donald Trump's approach at any time, who boasted of quickly bringing about a ceasefire.
For Putin, the war can only end in one way - Ukraine's capitulation; any other situation would be a huge political failure for him that would threaten his position.
Even with huge losses, the Russian president will be willing to fight to maintain his authority and control over citizens, suppressing any form of opposition.
Conquering Ukraine would be the only way for Putin to present himself as a victorious leader to the Russians and maintain his political influence for a certain period. After that, he will need a new war.
Europe, 800 Billion Euros for Defense
The crisis at the White House, when Trump and Vance attacked Zelensky, although "a great TV show," as the American president called it, unsettled the Russian leader due to the speed at which the European Union and the United Kingdom reacted, trying to compensate for the US's withdrawal from the scene.
"The first part of the ReArm Europe plan is to free up the use of public funds in the defense sector at the national level. Member states are prepared to invest more in their own security if they have the necessary fiscal space. And we must allow them to do so. That is why we will propose shortly the activation of the national exemption clause from the Stability and Growth Pact. This will allow member states to significantly increase defense spending without triggering the excessive deficit procedure," announced Ursula von der Leyen, President of the European Commission.
EU leaders have proposed a mechanism for states to use additional funds for defense of 650 billion euros over the next four years and the creation of a financial instrument through which the European Commission will offer member states loans of 150 billion dollars for defense investments.
In 2024, Russia's military budget was 100 billion dollars, the European Union's was 343 billion dollars, and the UK's was 70 billion dollars.
American Strategy Hasn't Worked
Donald Trump, a close ally of Russia since his first term, caused a diplomatic crisis at the White House, hoping to create a crack in international support for Zelensky but also to find a scapegoat for the failure to achieve a ceasefire.
However, the Trump-Vance strategy did not work. It triggered a major crisis within the Republican Party, a rapid response from Europe, and a decrease in the global influence of the US, whose administration supports an aggressive state.
Ukraine can resist for at least three months without American military support, according to the most pessimistic experts. The correct question now is whether the European Union and the United Kingdom can quickly build an international coalition to replace US efforts.
The first steps have been taken, and the answer to this question will truly determine peace. Without offering Putin a substantial reaction force and providing substantial security guarantees, there will be no end to the war.