During the Cold War, the exclave of West Berlin, isolated in the middle of Communist East Germany, was regarded as one of the most dangerous potential flashpoints for a conflict between the Soviet Union and the West. Indeed, Joseph Stalin’s blockade of land access to the city in 1948-49 came close to triggering a new war, until the U.S. and Britain proved able to supply the population by air.
It is a pity, if not altogether surprising, that Western leaders gave no thought to this history before extending NATO membership to Poland and Lithuania, thereby isolating the Russian exclave of Kaliningrad (Koenigsberg in the former German East Prussia) behind NATO lines.
It is now common for Western security analysts to describe the “Suwalki Gap” in northeast Poland, situated between Kaliningrad and Russia’s ally Belarus, as the most dangerous point in the growing Russia-NATO confrontation. Yet they carefully omit to recall that it was NATO, not Russia, that made it so.
The acute strategic vulnerability of Kaliningrad is one key reason why growing fears that Russia may “test NATO” by seizing the Estonian town of Narva, on the Russian border, are so absurd. For one inevitable result of a Russian invasion of NATO territory would be a NATO blockade of Kaliningrad by land and sea. As a Russian security expert remarked to me, “Does anyone in the West seriously believe that Putin or any other Russian leader would risk losing Kaliningrad for the sake of gaining Narva, or having to launch a nuclear war in order to save it?”
Or as former Latvian Defense Minister Artis Pabriks has undiplomatically but accurately stated, "We have always assumed that, if such a war were to break out, Russia would cut off the Suwałki Corridor. But somehow we don’t consider the possibility that, if Russia were to attack, [Kaliningrad] would be the first to be overrun [by NATO forces]. And then there would be no Suwałki Corridor left."
Kaliningrad is the headquarters of the Russian Baltic Fleet and a base for Russian medium-range nuclear missiles. It is also internationally-recognized Russian territory. In U.S. terms, it is as if Pearl Harbor found itself isolated in the middle of Chinese-controlled territory. The progressive expansion of NATO since 1989 to East Germany, Poland, the Baltic States, Sweden and Finland has also turned the Baltic Sea into a NATO lake, with Moscow’s control reduced from the whole eastern and southern shores that it controlled during the Cold War to just Kaliningrad and St. Petersburg.
President Vladimir Putin and the Russian government have stated recently that if NATO blockades Kaliningrad, Russia will respond with nuclear weapons if necessary; every member of the Russian establishment with whom I have spoken has said the same. NATO Secretary General Mark Rutte, displaying the smirking, strutting frivolity that he has made his trademark, responded that he does “not take this seriously.”
But this threat is serious. Moscow would regard a NATO blockade as a direct act of war. Equally important, with most of the Russian army bogged down in Ukraine, Russia lacks the conventional military force to ensure it can hold Kaliningrad against ground assault or to attack from Belarus, defeat the Polish army and break a siege. Before the invasion of Ukraine, the Russian 11th Army Corps, based in Kaliningrad, had a nominal strength of 12,000 to 18,000 men, backed up by a brigade of naval infantry, but a good many of these troops are reported to have been deployed to Ukraine and lost there. The Polish army has 100,000 men under arms plus 40,000 reservists and is rapidly building up its firepower.
As the U.S Center for Naval Analyses asks, “Kaliningrad: Impregnable Fortress or Russian Alamo?” The consensus among members of the Russian establishment with whom I have spoken is therefore that, in the event of a NATO blockade, Russia would have to issue a nuclear ultimatum immediately and carry the threat through within days if NATO did not back down.
It may seem that NATO countries could not possibly be so crazy as to run the appalling risks involved in imposing a blockade on Kaliningrad; but in fact they have twice suggested moves in this direction. In June 2022, Lithuania announced that (in violation of a previous agreement with Russia) it would impose a ban on the transit to Kaliningrad of goods subject to European Union sanctions, including oil, coal, metals, construction materials and advanced technology — around half of the exclave’s import needs, according to the provincial government of Kaliningrad. After harsh Russian threats of retaliation, the EU backed down and declared that the sanctions would not apply to rail transport.
In June 2025, Sweden announced that it would carry out checks on ships belonging to Russia’s so-called “shadow fleet” not only in Swedish territorial waters, but in Sweden’s maritime economic zone. Together with those of the three Baltic States, this covers the whole of the Central Baltic, meaning that the Swedish announcement threatened to blockade St Petersburg and isolate Kaliningrad by sea.
The Swedes and Balts quietly backed down after Russian threats of military intervention to protect the ships and the dispatch of a Russian fighter plane to deter an Estonian patrol boat from boarding a tanker. It is hardly surprising, however, that Moscow is acutely neuralgic about the possibility that this strategy might be resumed.
Polish Foreign Minister Radek Sikorski stated only last month that, “We should not be thinking about our confrontation with Russia only as being confined to Ukraine.
“I was in Latvia just three days ago on a Polish base, we have a tank company there, and … there are no troops on the other side. We closely monitor, as you may imagine, the Kaliningrad exclave. There are hardly any troops there,” Sikorski said. “I’m suggesting we should exercise so aggressively on our side as to make … [Putin] uncertain of what we will do, and so that he needs to draw forces away from Ukraine.”
The ironic thing about this statement is that at the very same time that Sikorski was saying Russia is so weak in the Baltic region that NATO can threaten it with impunity, other Polish officials were warning of the likelihood of an impending Russian attack on NATO to “test” the alliance.
Given the blind recklessness and irresponsibility of such statements and moves, it is therefore just as well that Russia has made absolutely clear what the consequences will be if NATO countries were to put these threats into effect.
It is common for Western analysts to dismiss such Russian fears either as “paranoia” or the result of deliberate manipulation by the Russian government; but a moment’s reflection on their own attitudes should bring them to an awareness of the falsity and hypocrisy of this charge.
A U.S. security establishment that goes into hysterics when a Chinese balloon flies over America is in no position to accuse anyone else of paranoia, and nor are European security figures who allow a few minor acts of arson to spook them into declaring that “we are already at war with Russia.” If the West blockades Kaliningrad, they may learn what a real war with Russia is like.
In old allegorical paintings of Prudence, she is often portrayed holding a mirror. This symbolizes her capacity for self-awareness and self-examination, that in turn leads her to modesty and a better understanding of others. For all our sakes, it would be better if European governments spent less time shouting in Russia’s face and more time examining their own.