Key point: The Spanish Civil War's political fault lines, weapons, and strategies were all what would be seen across Europe once Nazi Germany invaded Poland. Here's how the war became a testing ground that foreshadowed the coming conflict.

A Mediterranean nation beset by military coup and civil war. A savage struggle marked by atrocities and fanaticism. Proxy war waged by outside nations pumping in men, weapons and money.

Today’s Syria or Turkey? No, it’s sunny Spain, now a peaceful member of the European Union, but eighty years ago the arena for one of the most vicious conflicts in history. The Spanish Civil War of 1936–39 is remembered today as a sort of Second World War-in-training, a playoff game before the championship match between Team Axis and Team Allies a few years later.

The Spanish Civil War began in July 1936 when Francisco Franco led a dissident group of staunchly conservative and Catholic generals, as well as half the Spanish Army, against the liberal, elected Spanish government. What should have been an internal military revolt like the recent attempted coup in Turkey swelled into an international struggle between democracy and authoritarianism, liberalism and conservatism, and communism versus fascism. In the end, fascism won.

In some ways, the Spanish Civil War belongs to a different era. We are accustomed today to slaughter inflicted in the name of God. Back then, the cause was ideology, the disputes over whether the world should be democratic or fascist or communist. Yet in other ways, the conflict seems all too familiar. Like today’s Iraq and Syria, the combatants fought amongst themselves as well as the enemy. The Nationalists were a collection of conservatives, monarchists and fascist Falangists. The Republicans were supported by a bizarre potpourri of socialists, communists, Trotskyites and anarchists, as well as international leftists such as the Abraham Lincoln Brigade from America. The “White Terror” of the Nationalists murdered two hundred thousand opponents, grimly dwarfing the fifty thousand or so victims of the Red Terror, conducted by Republican death squads that were led by Soviet NKVD secret police.

The Nationalist rebels were supported by Nazi Germany and Fascist Italy—not just with arms, but with troops and aircraft. German transport aircraft flew Nationalist soldiers from Spanish North Africa to the mainland. More important, Germany dispatched the Condor Legion, a twelve-thousand-strong force equipped with bombers, fighters and tanks. Not to be outdone, Mussolini sent fifty thousand Italians. By comparison, perhaps ten thousand Russian troops might have been committed to today’s Syrian Civil War.

Though the Spanish Civil War is viewed as a proving ground for World War II, that’s not strictly true. The mountainous Spanish terrain precluded the massed tank attacks and deep-penetration mechanized offensives of World War II. But it did provide invaluable experience to Hitler’s military, especially the Luftwaffe. Germany had the chance to test weapons it later used in World War II, such as the He-111 and Do-17 bombers. Legendary Luftwaffe fighter aces such as Adolph Galland and Werner Molders learned their craft in Spanish skies, devising deadly air combat tactics such as the “finger-four” formation. Not surprisingly, Italy didn’t fare quite so well, such as when the Republicans defeated an Italian force at the Battle of Guadalajara.

With typical fascist unity, Franco did not reciprocate Hitler’s generosity. In 1940, with France conquered and Britain fighting alone, the führer attempted to persuade Franco to declare war on Britain. The Spanish dictator successfully fobbed him off, leading Hitler to declare that he would rather endure a visit to the dentist than negotiate with Franco.

For the Republicans, the world turned its back. Some British officials preferred a fascist-leaning Nationalist regime to a leftist one. Britain and France imposed an arms embargo on both sides, but with the Nationalists receiving German and Italian weapons, the freeze only hurt the Republicans (just as the post-1967 British and French arms embargo in the Middle East only hurt Israel, rather than the Soviet-supplied Arabs). Only the Soviet Union would provide weapons and advisers.

Soviet officers also had the opportunity to learn modern combat, though naturally Stalin had his Spanish Civil War veterans executed for fear of ideological contamination. Yet not all the lessons were correct. Top Soviet military leaders concluded that massed armor was ineffective, and that tanks should be dispersed in small packets to support the infantry, a doctrine later smashed by German blitzkrieg tactics.

At times the war veered into the farcical, as when Italian submarines sank neutral ships transporting supplies to the Republicans. Instead of condemning Italy, Britain and France blamed “pirates” (as if Blackbeard was a U-boat commander), and began convoying ships in the Mediterranean.

Perhaps the most enduring legacy of the Spanish Civil War is its iconic images. We have Pablo Picasso’s haunting painting of the terror bombing of Guernica, Robert Capa’s classic (and now thought to have been staged) photo of the death of a Republican soldier, George Orwell’s Homage to Catalonia and Ernest Hemingway’s For Whom the Bell Tolls.

But who the bell really tolled for was the Western democracies. Hitler and Mussolini had committed jackboots on the ground to overthrow a democratically elected government. Though it would probably not have deterred Hitler’s quest for war, world support for the Republicans would have signaled determination against the rising fascist menace. Yet if Britain and France wouldn’t lift a finger to help Spain in 1936, then why should they fight to save Czechoslovakia in 1938? No wonder Hitler expected the Western powers to stay quiet when he invaded Poland in 1939. The fuse for World War II might have been lit in the hills of Spain.

The Spanish Civil War still leaves us with a question: What price stability? Some believe that we need strongmen like Saddam Hussein and Bashar al-Assad to bring order to the Middle East. There was indeed order in Spain after the civil war. Under Franco’s rule, Spain was mostly peaceful (except for the Basques), and a U.S. ally that hosted American nuclear missile submarines. It was also an authoritarian regime with censorship and political prisoners.

Is Franco the sort of ruler we want for the Middle East today?

Michael Peck is a contributing writer for the National Interest. He can be found on Twitter and Facebook. This first appeared in 2016 and is being reposted due to reader interest.

Image: Reuters