“The dictators intervened and the democracies did not — that is the history of the Spanish war in one sentence.” Fair?

THE SHORT ANSWER

• Versailles’ last physical restraint was psychological. The demilitarized Rhineland worked only as long as Germany believed violating it meant war. By March 1936 Hitler had strong evidence it did not: the Abyssinian crisis had shattered Stresa, Britain had signed away naval limits, and France — whose military doctrine was entirely defensive, built around the Maginot Line — had no plan on the shelf for a limited counter-march. He also had a legal fig leaf ready: the Franco-Soviet pact, ratified that February, was “encirclement,” so Locarno was void. Each gamble recycled the proceeds of the last.
• France would not fight alone; Britain would not fight at all. French intelligence roughly tripled the size of the German force; the general staff answered every ministerial question with “general mobilization” — political suicide weeks before an election. Britain, the co-guarantor of Locarno, made clear it would not support action; Eden proposed negotiation. The deeper cause: French security thinking had been outsourced to allies and concrete since 1918, and neither could march. It is the clearest case in the decade of a war-winning move declined at near-zero military cost.
• Spain’s war was internal first, international second. The Republic of 1931 had attempted, in five years, land reform, army reform, regional autonomy and the separation of church and state — each making mortal enemies; the February 1936 Popular Front election was won narrowly amid mutual fear. The rising of July was planned by Spanish generals for Spanish reasons. But the interventions transformed it: German and Italian arms made Franco’s victory possible, Soviet aid and the International Brigades prolonged resistance, and the war became — as everyone at the time said — the dress rehearsal in which the coming war’s sides, weapons and moral abandonments were all tried on.
• Non-intervention institutionalized the double standard. The Anglo-French embargo applied evenly to an elected government and to rebels — formally neutral, materially decisive against the side with no other legal suppliers. The policy flowed from real fears (a general war, Bolshevism in Madrid, French internal division) but its effect was to teach both dictators that the democracies would police their own citizens’ aid to a fellow democracy more energetically than fascist expeditionary corps. Blum wept when he signed; Hitler drew conclusions.

WHAT IT CHANGED

Belgium bolts, the Maginot logic breaks. Watching Locarno die unenforced, Belgium renounced its French alliance in October 1936 and returned to neutrality — so the fortified line France had built stopped at exactly the border the Germans would come through in 1940 (Ch. 9). Deterrence failures cascade: each ally that hedges makes the next more likely to.

The Axis names itself over Spanish battlefields. Joint intervention in Spain gave Berlin and Rome their first working partnership — the “Rome–Berlin Axis” is coined in October 1936, the Anti-Comintern Pact with Japan follows a month later. The coalition of the revisionists assembles not by treaty first, but by practice.

Air terror is normalized before the war begins. Guernica, and the Japanese bombing of Chinese cities the same year (Ch. 6), put civilian bombing into the world’s repertoire while the world watched. The bomber-dread that shaped Munich — “the bomber will always get through” — was manufactured in Spain; so was the operational skill of the Luftwaffe crews who would open the next war over Warsaw.