Thats a long and complex question. Two items were:
In August 1939 the French leaders were completely convinced the nazi government was completely untrustworthy. Many people forget the German occupation of Prague, and replacement of the Cezch government with a German governorship, was a complete abrogation of the spirit of the Munich agreement, if not the letter. Renaud & his cabinet had zero confidence that any further treaties or agreements with Germany would be of any value.
Ten months had brought France closer to the level of military readiness Gamelin & his peers promised. The government were hearing reassuring reports about progress in rearmament. On of the reasons the French acquiesced in betraying Benes government were the pessimistic report on readiness from Gamelins office in the summer and autumn of 1938. In August 1939 Renaud could look at reports of great things to expect late in 1939, and greater things in 1940.
There were a lot of other factors, but these two appear often in the internal correspondence of the Cabinent, and records of the Deputies.
Thanks for paying some attention, but the core issues I was hoping someone knowledgeable about late 1930s French politics are still not being addressed. This is all entirely in the question of semi-technical responses to Hitler's actions, relating to politics indeed in the sense of people knowing Hitler cannot be bargained with.
On the other hand, it is my perception that a great deal of French defeatism came from a place of political conservatism--to wit, a big segment of French public opinion, particularly within the conservative faction of the military, that more or less fascist authoritarianism was actually a good thing. Post-capitulation these politicians, most notoriously Laval, and more tragically Petain, were naturally elevated by Hitler to power and were left with some freedom to pursue a reactionary agenda insofar as it met with Nazi approval. That some French officers of high rank were in these circles, including of course General Petain, is quite notorious. Similarly the Czechoslovak regime was, per Munich terms, purged of the perhaps somewhat counterproductive but definitely resolved in patriotism Benes, who had to flee into exile before Hitler ended the drama by overt invasion--at that point the reduced defenses were quite incapable of repelling the Wehrmacht in any meaningful sense, quite aside from issues of defeatism, but it is also true that the regime in Prague was handpicked by German approval to favor rolling over for him.
Fascism is a funny thing of course, as might be expected of something so very perverse. Its logic, such as it is, is premised on ultranationalism, so that one might suppose that the most resolute enemy of German fascism in France would be French fascists. But in fact despite the fundamental logic of ultranationalism, Hitler's Naziism, expressed in purest form in the SS, was flexible enough to incorporate a backdoor form of internationalism via the Aryan ideology, which dismissed democratic norms categorically but substituted a scientifically as well as morally insane racism that could be held, by people flexible enough, to allow for cherry-picking an elite minority within any nation as sufficiently racially "pure" enough to serve as privileged subjects of the greater Reich. The SS thus went about recruiting people of all their conquered territories as "hidden Aryans" and inducting them into military groups as the Waffen-SS, and promoting "volunteers" (and I do suppose most of them were volunteers in the ordinary sense) for their crusade against the Soviets--even ethnic Russians could be so recruited as Vlasov's infamous corps demonstrates.
My question about 1938 versus 1939 stems from the OP premise--I can't be arsed to read it again right now and the widespread assumption Britain too is in the anti-Reich alliance might be unwarranted, but the entire premise of this thread is that for whatever unexplained reason, the French government of 1938 stands by their treaty with CZ rather trying to weasel out. We can agree to disagree about how wise or unwise it was for the two dominant western "satisfied" colonial superpowers to defer conflict by more than a year (or at least a year, if we take to the widespread but not OP mandated assumption Hitler waits until inconclusive negotiations fail, until September or October, rather than simply attacking in May with no warning as I think he would have done if
he had been as confident as some here he enjoyed real superiority so early). But certainly France had a clear treaty obligation, and while shrewd and cold-blooded studies of the subjective preparedness of German versus Western and CZ soldiers to fight, and the respective kit and doctrine in hand, might show the western alliance as much weaker than they looked on paper, certainly France still had a massive paper strength that it would hardly be reasonable to expect Hitler to be able to overturn as handily as he did OTL. So the OP has some homework to do accounting for an ATL French decision not to be daunted and declare that Hitler had already done plenty to demonstrate untrustworthiness and an insane aggression that needed to be sharply checked--but certainly these things were already facts, Munich or no Munich. The occupation of the Rhineland, the Anschluss involving as it did the assassination of the established ruler of Austria and violation of the Versailles imposed strategic separation of German lands into two nations, along with repudiation of Versailles itself, the military buildup itself far past levels of reasonable capacity for self defense (not disputing that Versailles levels were insufficient for that--that was kind of the point after all!) and the expressed principle of Germans needing to be brought into the Reich, which had deeply ominous implications for all nations of southeastern Europe (for ethnically and culturally German population centers were scattered all through the southeast of the entire continent, indeed even deep in Soviet territory as far east as the Volga)--were all ample for someone who regarded the fascist way as repugnant and inhumane and inimical to Enlightenment civilization, and should also be ample for the most pragmatic patriot with no regard for such lofty ivory tower ideals but with a shrewd eye on strategic balance of power. France depended in part on massive self-armament in the form of the universal levy en masse of the male citizenry as trained conscripts who had all done some years service in the national army, but also on a system of alliances with numerous Eastern European nations, notably Poland and Romania, not just against the rise of German power but originally as a mutual interest buffer against Soviet power. The alliance with Czechoslovakia was key; however much one might prove the improvement of real French capacity in terms of training, doctrine, and arms over the year that France bought with sacrificing that, the fact remains that France was ignominiously defeated in detail once German power turned west. We have a much harder time measuring the effect of morale, but certainly it cost France a great deal of self-respect to trade off the fate of the people of Czechia and Slovakia, and shook the confidence of all her other client states in the east. I think we cannot set morale at naught.
Concretely in France, we see in OTL's failed resistance a lot of evidence of inflexible thinking along with defeatist panic, and much of that is the fish rotting from the head down, as is proverbially generally the case. There is some plausibility to the argument that in 1938, thinking would be still more rigid and flexible, innovative response might have been still harder to come by--but no matter how impressively we enumerate what arms the Germans do have in hand, the fact remains that in all of the categories mass of arms, technical development of same, battlefield experience, and sheer numbers of men the Wehrmacht too is weaker in May or even September 1938 than a year later. They must first go through the meat grinder of attacking the Czechoslovakian defenses and it is by no means a slam dunk they get the help of Hungarian forces to do that, not at least until the turning point is reached and CZ is clearly already collapsing. This will put some conquered resources at their disposal but not nearly as effectively as OTL where they have a whole year to assimilate undamaged, intact Czech supplies as well as production facilities; a stiff CZ resistance will deplete these and damage what is left. It seems dubious to assume that Poland just sits it out, in view of Poland's deep commitment to the French alliance--an alliance that is not cast into the mud of Munich as in OTL. At the very least Hitler must deploy some forces to screen his long frontiers with Poland, assuming that the Poles in fact betray their alliance and do not help France as promised. More realistically, Hitler must settle the question of Poland forcefully. Any benefit he gets from plundering either Czechia or territories taken from Poland is far offset, in the short run, by losses the Wehrmacht suffers doing so--that in turn offsets the argument that the Wehrmacht is green, if they can put paid to both Czech and Polish resistance they will not be green anymore...but they will be decimated.
And so, while France might be at a worse disadvantage both in paper terms of the shrewdly evaluated worth of what arms and men they have standing ready, and arguably as well even less prepared to deal intelligently and flexibly with the new military thinking the Wehrmacht has been drilled in, there remains another dimension of morale to consider, which is the cohesion of France on a political level. That is what I have asked for further insight into and which has not been responded to.
My reason for believing the 1938 government rested more firmly on the left and leftish liberal center of French public opinion has for its main concrete basis the fact France was in fact openly aiding the Republicans in Spain. French conservatives would be quite upset by this, for of course the Loyalists included factions that were infamously left-radical and viciously anti-clerical, whereas French conservatism includes much lip service (we won't get far discussing how deeply sincere their sense of religion would be in terms of passionate Christianity, but there is no doubt they tended, with I suppose some atheist but otherwise right wing exceptions, to hold that as a secular institution the Catholic Church was crucial in anchoring a suitably "orderly" public mentality) to the vital role of the Roman Catholic Church, the enemy of many a Loyalist and perhaps many of the French volunteers as well. But unlike Britain, which I gather basically made it easier for the developing Axis side to aid the Nationalists, France as a state was nevertheless firmly on the Republican side.
By extension, I thus imagine that the particular constellation of French leadership in the top positions in 1938 were also opposed to Nazi Germany not just on patriotic and strategic grounds but on the ideological grounds of the spectrum from liberalism to left-radicalism that despised Nazi ultra-rightist highhanded methods, the so-called "positive justice" much embraced by German police and perhaps envied by many a cop in more liberal nations that permitted authorities go snipe-hunting for people they had always disliked as dubious social elements, round them up and imprison them (perhaps in the West it was not generally understood how much worse than that it had already gotten and would become; surely to any fair-minded person just sequestering the "undesirables" in camps on mere suspicion they might make trouble ought to be outrageous enough); the raw militarism mocking the painful lessons of the Great War in the horror and futility of war; all this atop French chauvinism against the dreaded "Boche" and the simple and straightforward legalism that observed Germany had been behaving quite badly by the standards of post-war civility, having defecated all over the generosity of "Locarno," and the hopes of an age of peace founded on peaceful negotiation in the League of Nations--all this adds up to plausible ground on which the right French leadership might have dug in its heels and decided they would fight with whatever they had on hand rather than tolerate another step in this pathological evolution.
We have as well the imponderable element of possible Soviet aid, which was being pursued OTL quite actively with Litvinov as the face of Soviet foreign policy pursuing a common front of Soviet and liberal powers against the rising tide of fascism. I leave the Russian factor out generally because it is so hard to see in logistic and strategic terms how Soviet power comes face to face with that of the Reich, which was accomplished OTL by the betrayal of the Popular Front line and of Poland.
But it remains on the OP to flesh out better just how resolve to fight happens in Paris, given political facts on the ground that OTL led to a year of appeasement with all the moral costs it incurred, however technically advantageous (and yet OTL, ultimately vain!) buying a year's time for arming up actually was. How does it happen? Do we most conservatively suppose the same leaders who OTL backed the Loyalists in Spain change their minds? Do we instead judiciously prune and rearrange French politics over the year or two preceeding to lay groundwork for a different mentality? Indeed while I have been lauding the French Left, I am aware that both broad ends of the traditional Left-Right spectrum in France were somewhat splintered--on the Right while OTL Vichy identifies large numbers of French rightists quite willing to collaborate with Nazi power, and in hindsight points some finger of guilt at their possible collusion via defeatism in the conquest, other French Rightists of the DeGaulle type would never surrender their patriotism to any foreign power, certainly not German. And on the left we have both the strong Communist bloc which proved so dangerously defeatist on orders from Moscow and the softer pacifist tendency that came out of the Great War quite pummeled. But OTL similar levels of the latter sentiment in Britain were dissolved quickly enough, are the French going to be that different? And here it would take a further OP presumption of Wayback Machine operation to bring Stalin around to a Ribbentrop-Molotov Pact a year or more earlier. By no means impossible as only Stalin's character governs there, but will Stalin turn away from the on-paper much stronger Western powers, if they reach out to him less ambiguously and beg his help in return for considerations such as consolidating the status of the Soviet Union as a legitimate global power these superpowers treat respectfully with as legitimate heir to Russian power?
So, does France decide to stand with Czechoslovakia, as this whole thread presumes it does, by just the existing OTL leadership changing its mind, or would it require we rotate some of those OTL leaders out earlier to present Hitler with a stronger, more resolved French leadership? Would France stand by CZ more firmly if its leadership shifts to the patriotic right, or is it more plausible the patriotic left of France is what is needed?
My preferences are plain, but I am asking people who know a fair amount about French politics in the mid and late Depression years to weigh in here.
On the battlefield, the relevant question is, would a different mentality in the ruling circles of the French government change the mindsets of OTL generals and field officers who might have been daunted OTL, to refuse to give up so easily? To this we add the observed fact that Hitler OTL got quite lucky in several ways in his victory over France--what are the odds the same rolls of the dice benefit him in the same or effectively equivalent ways, versus France doing better within the range of plausibility? But here I focus on the political variable as it supports morale. Will it make a difference in the fighting resolve of French forces that their country is acting honorably, in a plainly just cause, and not merely out of self-interest alone? Will the central government promote different generals, and remove others, with a less clouded mentality? And if defeat is still in the cards, will it be as abject as OTL or will France fight on in exile?
Clearly Hitler cannot defeat France without attacking Belgium and doing that ought to bring Britain in for sure, perhaps not in terms that provide risking British skimpy ground and air forces embarked to the Continent, but at any rate Germany will lose access to the seas outside the Baltic, and that harassed by RN submarines. Getting access to the Med involves bringing in Italy which will require the demonstrated collapse of France (which also of course gives direct access to the Med). If France does not fall, Hitler is seriously confined and if Poland is eliminated as a threat then unless this is accomplished by "Finlandizing" Poland, that is so intimidating its leadership the Poles dare not take action against him, it brings Reich forces up against Soviet ones. This is Hitler's ultimate intention of course, but dare he do it in this ATL without having the benefit of about two years of Soviet imported goods along with his looting the continent starting with Czechia? I believe starting a year earlier he cannot fold Norway into his conquests and so Sweden too is much more in play than OTL. There are factions in Sweden, more than other Scandinavian nations I think, that might go for a Nazi alliance spontaneously, but I still think they are overwhelmed by others who would prefer not to do this and so hold the country firmly neutral.
All that is a digression from the focus of this comment but it is somewhat relevant to the question--how would the politics of a French regime that stands by Czechoslovakia change the military strategic equation? My belief is that it would help France stand more strongly, especially if it is a left-center regime opposed to Nazi rule on deeply ideological as well as patriotic grounds, and has the asset of a sympathetic Loyalist Spain at her back. In such a TL the narrative of liberalism standing firm against pathological right wing extremism in solidarity is much stronger, and the possibility the Russians come in a generally helpful way is strengthened in the longer run. In this context I think Hitler is overall clearly weaker.
And that I think is exactly why OTL Hitler did not in fact simply go ahead and move to crush Czechoslovakia OTL in spring 1938, without stopping to play "Mother, May I?" with France and Britain first. The possibility exists that OTL, Hitler was prepared to fight if the Western powers did not capitulate diplomatically, I suppose; in that limited sense Hitler judged himself ready enough. But clearly it was a limited and not very confidence-inspiring sense, because at other phases of his career before and after he did not turn to diplomatic negotiations except after the fact of some bold move of his to defy the powers from a position of fait accompli. Here, and only here, he allowed talk and diplomatic to and fro to process through spring, through summer and into fall, gambling that pure intimidation would win him his goals without a shot fired. Why?
I think
Hitler judged he would be better off fighting a year later.