The butterflies aren't all bad for the Allies. A quick victory gives a few years for the regime to be installed and it could easily drift more to the Allied orbit out of the crushing economic weight around it, and with less influence from the Germans and Italians. The French exported war material to Spain, so save some of this for themselves - although I am doubtful that that does anything, given that the stuff they exported was broadly obsolete and they badly used their obsolete material during the Battle of France, and it would have presumably given them some money and export revenue.ore importantly is that the war in Spain was a great distraction for Britain and France, whose parliaments spent much more time dealing with Spain than contemplating what to do about Central Europe, and the French in particular were terrified about the prospect of being surrounded on all fronts.
"It would be difficult to exaggerate the impact of the Spanish war on French policy making. French preoccupations with the conflict helps to explain the capitulations in central and eastern Europe in 1939. The military situation created by the conflagration was a terrifying one. It was assumed in Paris that in the event of a Franco victory, France would be encircled ba triple alliance of Germany, Italy and Spain. In August, Delbos said that 'he had every reason to fear that General Franco had offered the bait of the Balaeric Islands to Italy and the Canaries to Germany, and if that materialised good-bye to French independence'44 Sea and air links with North Africa might easily be cut by air and naval forces operating from bases in the Balaerics, not to mention the danger to the land frontier of the Pyrenees. Moreover, a third of the French army was stationed in North Africa and survival in war would depend on the speed and safety which troops could be transported across the western Mediterranean.45 For France, the Spanish war began a war of nerves which lasted until the attack on Poland in September 1939. 'Europe is on the verge of general war', declared Delbos on 28 November, 1939.46 A month later, Count Welczeck, German Ambassador, told of:
the downright hysterical nervousness which has been evident among the public here for several days and has started crack-brained rumours circulating regarding the inevitability of a war, simultaneous military attacks on France from the east and the south planned by German.47
The Spanish imbroglio had two consequences for French foreign policy. First it strengthened the dominant role of Britain in the entente. The nightmare of encirclement by Fascist dictatorships made the French cleave closer to their ally. Secondly, the strategic uncertainty created by the war practically dictated the retreat from central Europe. Presented with almost simultaneous threats to her Mediterranean position and to geogrpahically remote allies in central Europe, France inevitably gave priority to her own security."
France and the Coming of the Second World War, pg. 45
Less focus on Spain, possibly more normalized relations with Spain, and if that succeeds less fear of encirclement could lead the French to take a more proactive stance against Germany. Of course, that relies on Spain's regime mellowing, but Franco's regime mellowed rather quickly too, until the Germans destroyed France. A faster victory by the rightists would give more time for relations to stabilize with France, and so might enable the French to present a more united front against the Germans. It is low probability, but butterflies could extend to something like a Czechoslovak war.