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In 2023, the NATO Baltic Defense College in Tartu, Estonia devoted its entire annual conference to the Interwar Period (1919 to 1939), a theme repeated at subsequent conferences sponsored by national militaries and academic societies throughout the United States and Europe. Western scholars and foreign policy analysts, provoked by Russia’s 2022 invasion of Ukraine, seem persuaded that we are living at the close of another interwar era — one in which an egotistical European power shatters a decades-long continental truce, established and upheld by an international rules-based order, by invading a smaller neighbor ostensibly to defend threatened national minorities. A new global conflict lies over the horizon, offering advantages to those with sense enough to perceive it and act accordingly.
Similarities between Ukraine (2014 to current) and Spain (1936 to 1939) have been raised by contributors in these pages as far back as 2015, and history is a pattern-making profession. Just a few months ago, the Hague Centre for Strategic Studies published a thoughtful, thorough analysis elucidating a number of powerful political and strategic analogies between these conflicts. While the work is excellently researched, it remains grounded in the conviction expressed above: that Spain and Ukraine represent regional manifestations of a resurgent authoritarianism seeking global dominance against divided democracies. But the flashiest analogies are often the most superficial, promoting stale, repetitive strategies and sleepwalking statecraft.
Our penchant for pursuing parallels with 1930s Spain, while well-meaning, will always take us astray insofar as our investigations are blinded by the dominant, stereotypical portrayal of its civil war. A more rigorous, open-minded comparison of these struggles will open the way for wiser courses of action that can liberate the West and Russia from prisons of our own making.
In particular, American policymakers should be attentive to wily leaders who support erstwhile “friends” against mutual rivals while accumulating advantages behind the scenes to become economically, militarily, and thus diplomatically more powerful, so that they may shape the contours of future conflicts.
Strategists, meanwhile, should guard against letting institutional bias and annual appropriations battles control their reading of Ukraine. Greater vision might be attained by refocusing their attention from the flashier antics of the bull or bear in the arena towards the short- and long-term consequences of bellicosity on national, regional, and global marketplaces.
For those unfamiliar with the Spanish Civil War, a brief synopsis is in order. The conflict erupted in July 1936, after months of increasing political violence emanating from a disputed national election, during which the governing Popular Front coalition sought to eliminate all legal means of opposing their rule. The Front’s equivocal response to the assassination of a key political figure, José Calvo Sotelo, triggered a revolt by army and naval, but not air force, officers. The remaining summer months witnessed the rise of various leftist militias alongside a government — or Republican — army, and the implementation of revolutionary social policies in loyal territory. The rebels, calling themselves Nationalists, spent the time reaching out to Mussolini and Hitler for materiel aid, and consolidated their ranks under Francisco Franco as Generalissimo and Head of Government.
Thanks to a historically innovative airlift from Morocco, courtesy of the Luftwaffe, Nationalists quickly seized the initiative in the south of Spain, but became bogged down from November 1936 to March 1937 in futile efforts to seize Madrid, which was held by a combination of Republican militias, Soviet Russian forces, and the International Brigades. Content with a toehold in the capital, Franco shifted north and spent the remainder of 1937 subduing the Basque region. The following year, he forced a corridor southeast to the Mediterranean, splitting the Republic in two. A failed Republican counter-offensive along the Ebro in the summer of 1938 paved the way for the Generalissimo to enter Barcelona in January 1939. A few months later, resistance in Madrid and Valencia collapsed, and the war ended.
Our first assessment of analogies begins at the level of policy: Are we looking at a civil war, a revolution, or a localized conflict within a wider international struggle? The perceived parallel is that the Spanish and Ukrainian conflicts started out as an internal “family affair” that quickly became proxy wars for global powers engaged in ideological struggle.
There is much to commend this analogy: The peoples of Russia have for centuries understood their core identity as a coalition of “White, Little, and Great Russians,” while Spain — the only European country without lyrics to its national anthem — is composed of, among other peoples, Castilians, Basques, and Catalans. In both instances, revolutions foreshadowed internecine violence (Maidan, 2014; the Second Republic, 1931), resulting in the removal of the country’s political leader (Viktor Yanukovych, King Alfonso XIII), who fled but critically refused to relinquish the legitimacy of his position. As triumphalist revolutionaries proceeded to implement the foundations of a brave new world, they produced counter-revolutionary violence. The injection of foreign support during the opening campaigns awoke an ideological dimension: “democracy threatened” by fascism, either by Hitler or by his presumed reincarnation, which, in the minds of Western outsiders, especially Americans, revealed the fight for what it truly was. Propaganda appealing to universal ideologies soon enabled anyone, anywhere, to imagine they were directly affected by events in Ukraine or Spain. For men who had missed out on an earlier Great War, this was their chance to participate in the true fight between good and evil.
Despite a compelling narrative, this analogy, which sees the true conflict as ideological and therefore international, overlooks a number of critical elements. First, there is the conflicting, even contradictory behavior from ideologically driven great powers in both contests (Germany and the Soviet Union in 1936, the United States in 2022), seeking to provide just enough support to persuade their own citizens of the leading role they were playing on “the right side,” while also being careful to keep the war limited and violence from spilling out of the region.
Second, there is the discrepancy between how our foes publicized foreign assistance, whether in the form of hardware or intelligence. Both Republicans and Nationalists actively downplayed “allied” assistance in terms of tanks, planes, and artillery on their own side, while hyping up the devastation wrought by foreign weaponry wielded by outsiders on behalf of their opponents. In 2026, we find the inverse: Ukraine and Russia actively celebrate material foreign assistance, whether in the form of NATO missiles, intelligence coordinated by the Ukraine Defense Contact Group in Ramstein, or simply sustained trade relations with India and China.
When it comes to foreign manpower, however, a different picture emerges. Republicans dedicated a large amount of propaganda to celebrating volunteers from other countries who flocked to take up arms in the Last Great Crusade, especially the 35,000 to 40,000 men comprising five International Brigades, organized by the Comintern. Indeed, the Brigades’ contributions were publicized in a nearly inverse relationship to their military effectiveness. On the Nationalists’ side, Germany and Italy combined sent at least 50,000 to 55,000 men, while additional volunteers hailed from minor powers such as Portugal, Romania, Ireland, and Finland. Fascist materiel support was impossible to hide, but Franco had more success downplaying the manpower angle (apart from the Italian Corpe Truppe Volontarie): He quickly subsumed the men into Nationalist units and shunted them off to secondary fronts.
Despite their assertions of civilizational jeopardy, neither Russian President Vladimir Putin nor Ukrainian President Volodymyr Zelensky has evinced a desire to attract and use foreign manpower. Current estimates suggest that no more than 20,000 to 30,000 fighters have entered the conflict on either side. Given the much larger size of these armies, such “recruits” are playing a proportionally less significant role, and their reasons for being there are decidedly less ideological. There is one “International Legion” largely made up of Poles and citizens from former Soviet Republics fighting for Ukraine, while for Russia, one finds a smattering of sub-Saharan Africans, Central Asians, and a sizable contingent of North Koreans who were placed in the supposedly quiet Kursk sector in 2024.
Instead of prioritizing ideological labeling, it would be far better to focus on the way categories of civil war, revolution, and proxy wars bleed into one another. Since the 1640s, world history is replete with civil wars that, if not quickly concluded, eventually become revolutions, while revolutionary policies beget violent reactionaries who plunge lands into civil war. Furthermore, civil wars tend to invite international participation, while major international conflicts of the twentieth century tend to provoke civil wars in the lands of both participating powers and proxies.
As we consider current or future outbreaks of internecine or international violence, we may want to hesitate before assessing these conflicts through rigid categorization or expecting them to stay within conceptual boundaries.
The second level of analogy comes at the level of strategy, how one decisively attacks the enemy’s center of gravity: Will it be by means of a sharp blow or slow strangulation? The former is invariably the preferred method. In traditional accounts, the provocateur parties of 1936 and 2022, perceiving themselves to be outnumbered in some way, seized the initiative to make a rapid drive on their opponent’s capital, hoping for a quick knock-out punch to end the war. Neither bid was successful as the defenders valiantly and unexpectedly held on, garnering international sympathy and creating a stalemate that turned the conflict into an unlooked-for and undesired war of attrition.
As with our policy analogies, there is much to commend here. The side that takes the initiative had years of experience in what we might call “frontier” warfare, whether the Spanish army in Morocco or the Russians in Chechnya, conflicts that were won by relentless offensive behavior over challenging terrain. The opening gambit in both cases was a push by elite forces in a two-pronged approach that got within the outskirts of Madrid and Kyiv. And both were unexpectedly halted by determined popular resistance in conjunction with foreign aid: Soviet equipment and international brigades worked with local militias to stop the Nationalists, and Ukrainian defiance, paired with anti-tank guided missiles and other Western materiel, blunted the Russian advance.
What this particular analogy overlooks, however, is the fundamental difference in how well Franco and Putin understood their opponents and their bases of support, which affected their conception of what this first campaign was to accomplish. Put simply, Putin, in 2022, fought the war he wanted rather than the war he faced. He chose to see the conflict in purely military rather than in revolutionary terms and, underestimating Ukrainian political cohesion and military capability, gambled on a decapitation strike against a state he assumed would collapse, not a conventional invasion.
Franco, on the other hand, fought the war he faced rather than the war he wanted. He knew that he was fighting a revolutionary enemy with deep-seated loyalties in countless villages scattered across the country. Franco’s unorthodox decision to detach columns from his Army of Africa to Andalusia and Extremadura while continuing to drive towards Madrid in the summer of 1936 has been censured by critics for violating the textbook principle “concentration of force.” Yet he felt it necessary, not merely as a preventative measure to suppress leftist resistance that would threaten his rear, but also to identify and install supporters capable of constructing a stable political alternative to the Popular Front’s chaos. What caused the stalemate before Madrid was more a matter of running out of trained regulars and the brutal, exhausting, and leveling nature of urban warfare.
This difference in strategic vision explains much about the actual details of the different advances — whereas the Russians sacrificed all for speed, moving over swampy terrain with very few practical roadbeds, vulnerable to missile strikes, drone attacks, and artillery fire that would ultimately do them in, Franco moved prudently, consolidating forces, securing his rear, and against the advice of many generals, opting to rescue the beleaguered Álcazar of Toledo, convinced that the powerful moral message of certain deliverance would generate new adherents to the Nationalist cause throughout Spain before the hardening of any frontlines.
In the aftermath of failed coups de main, opponents typically shift their focus towards economic dimensions, attempting to strengthen what logistics aficionados since the days of Cicero have called “the sinews of war.” Here, the need to acquire and mobilize resources and labor and to deny these same tools to your enemy calls for a more robust statecraft than most military men are willing or able to undertake.
Compounding matters, none of our factions could hope to resolve their conflict without acknowledging their dependence on the desires of larger economies. In 1936, loath to be dragged into a conflict of uncertain nature, intensity, or duration, Great Britain composed a non-intervention agreement, prohibiting materiel aid to either Republicans or Nationalists. Italy, Germany, and the Soviet Union, among dozens of other countries, promptly voiced their support and even more promptly set about violating it. The arrangement, despite its veneer of neutrality, invariably benefited the Nationalists. France, under pressure from Great Britain, only let a trickle of materiel cross the border to the Republicans, meaning Soviet aid had to come via the Mediterranean, until that too was halted by Italy’s Regia Marina and Nationalist bombers. Worse, Stalin’s high-handed plundering of the Republican gold reserves in 1937 had a crippling effect on that government’s ability to raise future loans. Meanwhile, Hitler and Mussolini had a vested interest in assessing the innovative technology and tactics used to support Franco. The latter was extremely generous, insisting his aid was a gift, and even the former delayed any hint of payback until the summer of 1940.
Russia and Ukraine, on the other hand, have found themselves increasingly dependent on the dancing threads of a global economic web decades in the making. This has taken the form of American and European sanctions on behalf of Ukraine, as well as closer economic ties between Russia and China, although how mutual that relationship is remains unclear. It is likewise conceivable that recent American activity in Venezuela or Iran may have unanticipated consequences on this phase of the ongoing war.
Since economies move at a slower pace than military maneuvers, it is common to connect this stage with attritional warfare, that bane of politicians, especially modern, democratic ones, where public commitment to war needs to be incited on a regular basis or, in the creative approach pioneered by the United States, selectively neglected and buried out of sight.
It is well worth pondering who, if anyone, benefits from attritional warfare. In the face of military theorists from Sun Tzu onwards who have strenuously warned against it, there may be countries that counterintuitively see benefits to prolonged attrition. Peripheral powers clearly took advantage of the prolonged conflict in Spain to become stronger on the world stage, none more than Nazi Germany. Despite remilitarizing the Rhineland in the spring of 1936, Hitler’s position on the international stage was still weak. Yet, by letting the Duce play the dominant role in supporting Franco, providing cutting-edge military equipment whose losses Italy could ill afford to replace, the crafty Führer stole a march eastward, instigating the Anschluss before moving rapidly to provoke the Sudetenland crisis. After Hitler’s masterful diplomatic performance at Munich, Italy would forever be the junior member of the Rome-Berlin axis.
By the end of the Spanish Civil War, Britain, France, and Italy were in a significantly weaker state vis-à-vis Germany, to say nothing of the Soviet Union, where Stalin had begun his Great Purge. Might there be a country or countries interested in using the prolonged Russo-Ukrainian war as a way of quietly empowering their position on the global stage, not only against perceived future foes but against their present allies?
The final analogy moves from strategic setback to operational opportunity: How have combatants sought to break situational stalemates?
The perceived parallel here is the resort to airpower to upset the established equilibrium, restore mobility, and secure a decisive victory. Certainly, propagandists in both wars have touted how impressive and deadly this threat can be. Spain witnessed the first strategic bombings in Europe, and Republicans played up the devastation wrought in Madrid, Malaga, Barcelona, and, above all, Guernica, an episode that dominated international attention for generations following Picasso’s decision to refocus and rename his composition on the disasters of war.
We may not have armadas of strategic bombers clouding the skies in the 2020s, but we certainly have the popularization and proliferation of drones. Their use has been most impressively displayed by the Ukrainians through Operation “Spider’s Web” in June 2025, which targeted long-range assets across five air bases deep inside Russia, while at least three times during the same year, Russia launched hundreds of Shahed-type drones in massive waves directed against Ukrainian energy and civilian infrastructure.
And yet, the allure of aerial power in the form of strategic bombing or drones not only overlooks the reality that far greater success was found in the application of a combined arms approach on the battlefield, but also draws attention away from the most important factor of all: the role of institutional culture in learning lessons from current conflicts.
From 1936 to 1939, six of the seven powers who played a pivotal role in the Second World War observed the air war in Spain intently, and all came away with different conclusions, shaped by and reinforcing the aggressive instincts peculiar to each military culture. By far the most interesting cases are Great Britain and the United States, where the Royal Air Force and the Army Air Corps remained wedded to strategic bombing to enhance their bureaucratic independence via increased appropriations, even if it meant excusing or blatantly ignoring evidence to the contrary. Other than the German military, it was the American Army observers in 1939 who came away with the most relevant conclusions vis-à-vis the next war: a combined arms approach of tactical airpower working in tandem with improved artillery and tanks alongside potentially mobile infantry, where each component was capable of adjusting their contributions to the shifting landscapes of war. And they, not the Army Air Corps, were proven right.
In the same vein, contemporary pattern seekers should be attentive to our services, studying the use of drones in Ukraine: Which are the most confident — and which are perhaps overconfident — in their conclusions?
As prescient as they had been in 1939, the United States Army may be falling prey to an infatuation with tactical drones. With armor increasingly perceived as obsolete even on favorable Eurasian terrain, the Army is pinning its relevance in appropriations struggles by touting the new weapon’s “vision” and networking capabilities with its already substantial artillery and air defense force. This new form of combined arms will achieve “drone dominance” on the battlefield. The fear is that such an overinvestment in controlling the opening gambit sacrifices true defense in depth and maneuverability should plans go awry, and pays scant heed to the incontrovertible relationship between system-complexity and fragility.
The U.S. Air Force seems loath to part from its nearly century-long bias for strategic airpower and remains committed to the production of far-ranging, technologically superlative, and increasingly expensive aircraft, the complete opposite direction of the short-range, low-tech, low-cost drone. While these machines have made attention-grabbing headlines from the Caribbean to the Strait of Hormuz, this approach overlooks secondary factors such as attritable mass and munitions exhaustion. Moreover, their undoubted value might accentuate an institutional desire to preserve these expensive delivery systems from the chaos of a future infantry battlefield.
If any branch seems to be learning proper lessons from Ukraine, it would be the Marine Corps, which observed Ukraine’s deliberate (and successful) adoption of small-unit tactics in 2023 as a way of breaking battlefield stalemate, and which has been developing “attack drone teams” in keeping with its traditional focus. The small size of this branch, however, compromises its ability either to procure resources or to implement them at scale.
Most concerning is that, despite the obvious stalemate in Europe, no service seems prepared institutionally — mentally, politically, or logistically — for anything but a brief conflict: certainly, the type of war all countries hope for, but only the wisest prepare against.
The oversimplistic rendering of both Spanish and Ukrainian conflicts as a clash of civilizations over international rules and norms, precipitating a global war in the near future misleads us in a number of ways.
Most critically, it suggests that a long war will benefit the defender rather than the aggressor. The Nationalists’ triumph shows that is simply not true, provided you can control or influence the vital pivots — weaponry in the 1930s, petroleum and electronics in the 21st century — of the international economy. Wars of attrition are not decided only at the front lines, where a breakthrough can lead to an utter collapse, but also in which side can sustain production, credit, and supply chains. It may be time to treat Chinese (and to a lesser extent, North Korean and Iranian) military and economic support to Russia as the true center of gravity in this conflict, not Putin or his close confidant, Alexander Dugin.
Second, we can be overawed by dazzling examples of cutting-edge technology. Rather than adopt boutique systems like the Italians which, while effective in a single theater, proved impossible to scale up and, worse, were environment-dependent, turning their army into a laughing stock by 1940, the United States needs to return its focus to mass: arms and munitions production, with numerous secure and effective transport to get them, and the men and women using them, across the oceans to future front lines.
It is quite probable that the next conflict involving the United States will entail fighting not exclusively over the broad steppes or mountainous terrain of a continental theater, but to some degree over the portion of the Earth’s surface covered by water. If, or when, that time comes, it will require a much different combination of arms and approaches than the one currently playing out on Ukrainian plains: one that accounts for not only geography, but also the particular values of America’s service branches and their military cultures, as well as those of our opponent.
Our human ability to discern patterns and create analogies should encourage us to be more perceptive, indeed, “in-sight-full,” about our world. Exercising this privilege is all the more vital in an AI-dominated age, where knowledge, to say nothing of understanding and wisdom, is becoming lost or unappreciated amidst a never-ending deluge of information.
Yet we should also be on guard lest our mindfulness about the past be turned into a mindlessness regarding future action, on the grounds that our created patterns foreordain a certain repetition or rhyming to human events.
Studying the wars in Spain and Ukraine or any other analogous conflict should offer to the historian, the strategist, and the policymaker something more than proffering clichés that tickle our ears. The greater reward is found in enriching our assessment of humanity’s shared experiences while generating an operational nimbleness for those needing to chart a wise way through our current situation.
Of the making of plans, and of their invariably going haywire, there is no end, as Ike and Mike have reminded us. American policymakers should hold in tension our national preference for regional security, which has remained largely static in the post-Cold War era, with an eagerness to develop diplomatic, strategic, and even operational dexterity, starting with a willingness to consider new allies from among former rivals.
This far-seeing and far-reaching approach is all the more necessary in light of our heightened focus on the nature and use of power to the exclusion of the traditional concept of authority (and therefore the forming and preserving of traditional relationships) now working itself out on national and global scenes.
Andrew Mitchell (Ph.D., The Ohio State University) is a professor of history at Grove City College. He has over two decades of experience researching and teaching Spanish and military history. Follow him on X at @humoredhumanist.
Image: National Defense Library via Wikimedia Commons
