Summary and Key Points: As Ukrainian drones batter Russia’s refineries and a fuel crisis spreads across the country, Vladimir Putin faces mounting pressure to hit back harder. Western analysts who study Russia’s escalation options have mapped what those blows could look like below the nuclear line, from cutting undersea cables to a covert land grab on NATO’s border. The most dangerous of them all is a direct conventional strike on NATO territory itself, the one move most likely to trigger the alliance’s mutual-defense clause. It is also, tellingly, the option Putin has the strongest reasons to avoid.
Putin Has Options to Escalate in Ukraine: No Nukes Needed
Russia is absorbing a great deal of punishment in the summer of 2026. Ukraine has struck all of its largest oil refineries, fuel is rationed in much of the country, and its oil revenue has fallen to a wartime low. That kind of pressure invites retaliation, and it raises a grim analytical question: setting aside the nuclear weapons everyone hopes will stay in their silos, what is the worst thing Putin could actually do? Western institutions that study Russian military doctrine have effectively answered it: a ladder with a clear and frightening top rung.
Su-35 Fighter. Image Credit: Creative Commons.
From Sabotage to a Border Gambit
At the bottom of that ladder is what Russia is already doing. For two years, Moscow has run a deniable campaign of sabotage across Europe, arson at factories, parcel bombs, and, most persistently, the use of a “shadow fleet” of tankers to sever undersea cables in the Baltic Sea. The Royal United Services Institute describes this gray-zone pressure as a deliberate test of how much NATO will tolerate, and the most likely near-term escalation is simply more of it, faster and bolder.
A rung higher sits calibrated military intimidation. Russia has sharply increased aggressive airspace and naval violations, forcing NATO to fly nearly triple the intercept missions it did in 2023, and pairs those provocations with nuclear rhetoric meant to unnerve rather than to kill. Above that lies the move the Belfer Center calls Russia’s most plausible sharp escalation: a limited, deniable ground incursion onto NATO’s eastern flank. The goal would not be to seize the Baltics but to fracture the alliance, to raise the question of whether member states would really risk war over a small territorial violation that matters intensely to some allies and little to others. If the answer looked uncertain, NATO’s central promise would begin to unravel.
The Worst Rung
The worst non-nuclear option, though, is the one Russia’s own strategists have written down. Western studies of authoritative Russian military texts catalog an escalation ladder whose upper rungs, still below a nuclear detonation, include direct conventional strikes on NATO soil: first against the weapons depots and logistics hubs that supply Ukraine, and then, more dangerously, against symbolic and political targets, command centers and government buildings, in the countries backing Kyiv.
This is the worst move short of nuclear war because it is the one most certain to cause exactly that. An overt Russian strike on a NATO capital or base would be a textbook trigger for Article 5, the mutual-defense pledge that treats an attack on one member as an attack on all. The Russian theorists who game this out are betting on a specific and chilling proposition: that faced with such a strike, Washington would hesitate to retaliate for fear of a nuclear exchange, and that the alliance’s guarantee would be exposed as hollow.
It is a gamble with the survival of nations as the stake, and it sits one short step from the threshold that this question excludes.
Su-35 Fighter from Russia. Image Credit: Creative Commons.
Why He Probably Won’t
Here, the analysis has to turn, because the worst option is also among the least likely, and saying otherwise would be alarmism. The consensus of Western intelligence is that Russia does not want a war with NATO and knows it would lose one conventionally.
The U.S. Defense Intelligence Agency assesses that Moscow “almost certainly seeks to avoid direct conflict” with the alliance, and researchers at SIPRI argue Russia is already effectively deterred, its threats partly a performance for a Western audience it hopes to frighten into pulling back.
A deliberate strike on NATO would invite the very confrontation Putin has spent the war trying to avoid.
The real danger, the analysts stress, is not a calculated bolt from the blue but an accident: a cable-cutting or an airspace violation that kills people, a shadow-fleet confrontation that spirals, an incursion that draws a harder response than Moscow expected.
The 2026 U.S. threat assessment sharpened its language this year to name deliberate conflict with NATO as a concern, yet even it declined to predict when.
The worst thing Putin could do, short of a nuclear weapon, is clear enough. The likeliest path to catastrophe is that no one quite decides to do it.
About the Author: Harry J. Kazianis
Harry J. Kazianis (@Grecianformula) was the former Senior Director of National Security Affairs at the Center for the National Interest (CFTNI), a foreign policy think tank founded by Richard Nixon based in Washington, DC. Harry has over a decade of experience in think tanks and national security publishing. His ideas have been published in the NY Times, The Washington Post, The Wall Street Journal, CNN, and many other outlets worldwide. He has held positions at CSIS, the Heritage Foundation, the University of Nottingham, and several other institutions related to national security research and studies. He is the former Executive Editor of the National Interest and the Diplomat. He holds a Master’s degree focusing on international affairs from Harvard University.
