Ukraine has wanted to join NATO for many years. The wish grew stronger after Russia attacked in 2014 and even more after the full war in 2022. Most Ukrainians support this step, and President Volodymyr Zelensky asks for it often. Still, NATO has not let Ukraine in.
The main reason is risk. If NATO accepts Ukraine now, the group may face direct war with Russia. Many members fear this fight. Some members also do not agree on the best plan.
This article looks at Why Ukraine Cant Join NATO at this time. It will explain the issue in three parts: politics, security, and world strategy.
Why Ukraine Can’t Join NATO — The Short Answer
Ukraine cannot join NATO now because it is at war. If NATO lets in a country at war, Article 5 would apply. This rule says all NATO members must defend that country. That would mean a direct fight with Russia.
The United States, Germany, and other key members fear this risk. They think it could make the war worse. Some also point to issues like corruption or military reform. But the main block is Russia’s pushback and NATO’s caution.
Ukraine’s NATO Journey
Quick facts:
- 2008: Ukraine asked to join NATO through a Membership Action Plan (MAP). Germany and France said no after pressure from Vladimir Putin.
- 2014: Russia took Crimea. Ukraine pushed again to join NATO.
- 2022: After the full invasion, Ukraine asked for fast-track membership.
- 2023: NATO said Ukraine could join without a MAP. But no invite came.
Unlike Finland and Sweden, who joined fast even with Russian borders, Ukraine is seen as too risky.
Key Entities Driving the Debate
- NATO (North Atlantic Treaty Organization)
NATO is a group of 32 countries. It is a military alliance. Its main rule, called Article 5, says an attack on one member counts as an attack on all. If NATO accepted Ukraine during war, members would need to fight Russia.
2. Russia and Vladimir Putin
Russia has opposed NATO growth for many years. It says NATO is a threat. Vladimir Putin uses Ukraine’s NATO goal as a reason for war. He claims it weakens Russia’s “sphere of influence.”
3. United States
The U.S. is the key player.
- Joe Biden: Sends weapons to Ukraine but avoids full NATO entry to stop war from growing.
- Donald Trump: Says NATO for Ukraine is a cause of war. If he wins again, he may block it fully.
4. Volodymyr Zelensky
Ukraine’s leader, Volodymyr Zelensky, says NATO is the only true safety. He asks allies often. So far, Ukraine gets arms and money, not membership.
5. Germany
Germany is often careful. It fears angering Russia. Chancellor Olaf Scholz refused to send long-range missiles. But his rival, Friedrich Merz, may give more support to Ukraine.
Article 5 and the Defense Dilemma
What is Article 5?
Article 5 is part of NATO’s main treaty. It says if one member is attacked, all members must see it as an attack on them. But it does not say exactly how they must act.
Why is this a problem for Ukraine?
If Ukraine joined during war, NATO would face Russia in battle. This could lead to a wider fight, even nuclear war. That risk is why NATO waits.
Strengths of Ukraine’s NATO Case
- Strong public support: Since 2022, over 80% of Ukrainians want NATO entry.
- Battlefield skill: Ukraine has modernized its army. It now uses NATO weapons with success.
- Democratic progress: Even during war, Ukraine keeps working on reforms in government and defense.
Areas of Concern
- Active war: Joining now could pull NATO into a direct fight with Russia.
- NATO politics: Hungary and Slovakia say no. The U.S. and Germany still wait.
- Corruption claims: Often raised, but many experts call this an excuse.
- Nuclear risk: Russia’s threats weigh heavy on NATO leaders.
Real-World Scenarios
- Case Study: Finland and Sweden — Both applied in 2022 and joined fast. Unlike Ukraine, they were not at war.
- Case Study: Albania, Bulgaria, Romania — These nations joined even with corruption issues. This shows the “corruption excuse” is not always applied.
- Scenario: Trump Presidency — If Trump returns, the U.S. could cut aid and block Ukraine’s NATO path.
Comparison Table: Why Ukraine vs. Finland/Sweden in NATO
| Factor | Ukraine | Finland & Sweden |
|---|---|---|
| War Status | At war with Russia | Not at war |
| Russia’s View | Core to its sphere | Less central |
| NATO Invitation | Blocked repeatedly | Accepted quickly |
| Public Support | 80%+ pro-NATO | Strong but less urgent |
| Article 5 Risk | Immediate escalation | Manageable |
FAQ: Why Ukraine Can’t Join NATO
Q1: What stops Ukraine from joining NATO?
Mainly the war with Russia and fear of triggering Article 5 obligations.
Q2: Does Ukraine meet NATO’s formal requirements?
Largely yes—democracy, civilian control, and reforms—but the war makes membership impractical.
Q3: Why did Finland and Sweden join quickly but not Ukraine?
Because they weren’t at war, so no Article 5 risk.
Q4: Could Ukraine join NATO after the war?
Yes, many members say Ukraine’s path is “irreversible,” but timing depends on peace conditions.
Q5: How does Russia view Ukraine in NATO?
Putin sees it as unacceptable, claiming it undermines Russian influence.
Q6: Does corruption block Ukraine’s membership?
Not really—other corrupt states joined. The main reason is fear of Russia.
Q7: Will Trump change U.S. policy?
Most likely yes—he openly opposes Ukraine in NATO and might reduce support.
Conclusion
Ukraine can’t join NATO right now because of its ongoing war with Russia and the fear of escalation under Article 5. While Ukraine meets many membership criteria and enjoys broad public support, the U.S., Germany, Hungary, and Slovakia continue to block its invitation. For now, Ukraine must rely on Western weapons and security guarantees, while its NATO future remains uncertain.
Author Bio
Written by: Author: John Mearsheimer
Publisher: Cato Institute
Published: March 6, 2025
Link: cato.org
References
- NATO Official Website – https://www.nato.int
- Kyiv Independent reporting on NATO membership debates
- U.S. and EU official statements on Ukraine’s NATO aspirations
- Expert insights from Mark Webber (NATO Defense College) and Stefan Wolff (University of Birmingham)
