This is precisely why Ukraine joining NATO could provide the best offer for enduring and effective peace in Eastern Europe. Not only would the country’s membership serve as a credible deterrent against future Russian aggression, it would also ensure meaningful burden sharing among NATO members.
And most crucially, even if a post-war settlement were to leave part of Ukraine’s territory under de facto Russian control, there’s still a responsible, realistic and reasonable way for Ukraine to join the alliance. To make this work, however, NATO and Ukraine would need to take three key steps:
First, as part of any peace settlement, Ukraine’s government would need to formally declare a “non-use of force” pledge to reclaim its occupied territories, and focus on a long-term diplomatic strategy instead. This shouldn’t be a problem, as Zelenskyy suggested this possibility already. Meanwhile, the pledge itself could be modeled after West Germany’s 1954 declaration on the eve of its NATO membership, which stated it “undertakes never to have recourse to force to achieve the re-unification of Germany or the modification of the present boundaries of the Federal Republic of Germany, and to resolve by peaceful means any disputes.”
Next, all of Ukraine’s internationally recognized territory — including the regions temporarily occupied by Russia — would be invited to join NATO, but only the areas outside Russian-occupation would receive the Article 5 security guarantee. Article 6 of the 1949 North Atlantic Treaty defines NATO’s area of responsibility as the “North Atlantic area, north of the Tropic of Cancer,” and as a result, U.S. territories like Guam and Hawaii, the U.K.’s Falkland Islands and France’s Réunion Island aren’t covered by Article 5. So, Ukraine wouldn’t be the first alliance member with partial territory excluded from the collective defense clause.
Finally, and perhaps most importantly, the alliance would then need to amend Article 6 to exclude Ukraine’s regions under Russia’s control. This amendment could be made during the accession-protocol process each alliance member undergoes before admitting a new country — and there’s precedent for this too. Article 6 was amended before Greece and Turkey joined in 1951, and in 1963, after Algeria’s independence, the North Atlantic Council acknowledged that Article 6 no longer applied to the Algerian Departments of France.
However, there are some who won’t agree with this process and will claim that countries are prohibited from joining NATO until any outstanding territorial disputes are resolved. But this is a common misconception that’s rooted in a poor understanding of the Study on NATO Enlargement, which was published by the alliance in 1995.
