I am currently a 11th grade student in Belgium, studying the WW1-WW2 interbellum and the transformation from pacification to aggression.
So in order to add some context: firstly we have the "failed" League of Nations, then the Locarno treaties (1925) (which caused Germany to join the League of Nations in 1926), leading on to the Kellogg-Briand Pact (1928). All these treaties directly condemn aggression and the League of Nations and Locarno tried to assure cooperation of threatened nations in case of war. We know the League of Nations failed because its sanctions were not always complied with and it basically became a "European winners club", reducing its effectiveness. An example of this are the "failed" disarmament conferences in 1932-1933 and the fact that Japan (1931) and Germany (1933) left the League of Nations without any strong repercussions. Locarno, however, should have had a bigger impact. It was fairly clear concerning border disputes (at least for western nations). We have also got the Dawes (1925) and Young plan (1929) in order to relieve Germany of some pressure pertaining to their (relatively) enormous reparation payments.
Now I understand that after the world financial crisis of 1929, and the inability of the Weimar Republic to function and operate effectively (my textbook argues this is due to lacking German democratic tradition - they have never had a proper democracy before then) Hitler has a fairly easy time using fear and despair to the advantage of his own politics. My question is, however, why did the world (at least the capable nations) not react more firmly to German expansionism (especially under a fascist regime which has clearly expressed its wish for "Lebensraum")? Nobody really cared about the German rearmament (1935), the occupation of the demilitarized Rhineland (1936) and the "Anschluss" of Austria (1938) (western nations only protested vocally). My textbook mentions that 1: the US didn't care for the EU as their policy was clear: isolationism and limiting itself to informal colonization. 2: France wasn't ready to fight another war as it had suffered so much from the previous one and the economical crisis (1929), 3: GB was too busy expanding its imperial empire ,4: the USSR and Germany maintained good relations after the Treaty of Rapallo (1922), they were still consolidating their own country, plus Stalin didn't really care for international politics and 5: Western Europe didn't think the war would extend to the west. I find it hard to understand why GB didn't act more aggressively: wasn't it them who were always afraid of European hegemony? During their entire modern history they have always attempted to prevent a decisive European concentration of power, and now one was building right before them. I understand that the GB thought communism to be a greater direct threat than fascism and certainly, I understand they were occupied with their colonial empire, but surely they must have seen this as a threat? Why did they think that Germany would halt its expansion with the appeasement politics in the Munich agreement (1938)? If anything, it made them believe they could get away with it. What made Poland the trigger? If western Europe wasn't sufficiently prepared for yet another war, then why did they decide to defend Poland? Was the cause due to Britain's fear of communism as the USSR was also involved?
tl:dr It was very clear Germany was craving for more. Most countries were not in a position to prevent this, the UK was. Why did the UK not intervene aggressively earlier?
Thank you for reading and I hope that it is possible to shed some more light on the underlying politics in this time.
Sincerely, a student
edit: some more context.
Hey! So it's one of those things that, in hindsight seems so simple, but the politics of the day led France and England to appease Hitler.
The Germans and the Brits had very differing views on what the Anglo-German Navy Agreement of 1935 meant. The Brits negotiated with the Germans realizing that the strict limitation to the size of their military, set out by the Treaty of Versailles was unjust. They also realized that Germany was in place to be one of the preeminent powers of Europe. While they were willing to admit that Versailles was too tough on Germany, they liked the idea of regulating German naval power. They formed these opinions while the Weimar Republic was still limping along, but Hitler's rise in 1933 did little to dissuade them.
Are we still dealing with the Hitler of Mein Kampf, lulling his opponents to sleep with fair words to gain time to arm his people, and looking away to the day when he can throw off the mask and attack Poland? Or is it a new Hitler, who discovered the burden of responsible office, and wants to extricate himself, like many an earlier tyrant from the commitments of his irresponsible days? That is the riddle that has to be solved.
That was written by Royal Marine General Hankey after his visit to Germany in 1933. The British government was absolutely clear eyed about the threat they faced, but they made the fatally incorrect assumption that power would make Hitler normal. (If you're a keen observer of American politics you may have seen this naivety on display by American voters who voted for Donald Trump, thinking the gravity of the office would chasten him).
The Germans, on the other hand, saw the Anglo-German Navy Agreement as the beginning of a possible alliance between Nazi Germany and Britain against the USSR and France, (a dream Hitler would hold onto).
Now, this agreement made Hitler seem like a reasonable guy -- or at least someone with whom the British could negotiate with. He'd agreed to keep his navy to 35% of the British navy!
At first, Hitler went about consolidating the German speaking people. While France had control of the Rhineland, it had only been in their control since the end of the First World War and the people there were very German. It's a pretty popular belief that the French were just too cowardly to react to this hostile German takeover -- but really i was a mix of a war weary public and the concern about the cost of mobilizing troops to defend the Rhineland that held the French back (faulty reports on the number of German troops also held the French back --reports said 300,000 troops while it was actually only 3,000).
When Hitler annexed Austria, it was the same deal. Governments denounced Hitler, but could not justify to their people pumping money and men into a war to liberate Austrians (who cheered the Wehrmacht as they entered the country), especially since liberation of Austria may mean full blown war with Germany.
In 1938, after annexing Austria, Hitler turned his sights to the Sudetenland, then controlled by Czechoslovakia. The crisis started in the Sudetenland with agitation by Sudeten Germans agitating for autonomy. Hitler rallied support for the in Germany and amassed troops at the Czech/German border. The only way British and French troops could come to the defense of CZ in the Sudetenland was through German territory, which would have sparked an all-out war with Germany. So, they agreed (Britain, France, Germany and Italy) to cede the Sudetenland to Hitler. The Czechs, not being a party to the agreement, obviously had every right to refuse, but it was made clear that they would stand alone against Hitler. (This was the Munich Agreement). Russia was excluded from the talks because of Chamberlain's distrust for them.
Finally, the 1939 invasion of Poland by the Nazis led to declarations of war by France and Germany because they were allied with Poland. This didn't mean, of course, that they rushed to the aid of Poland. It was more of a formality that saw very little actual conflict, the Phoney War as it would end up being called, which came to an end when the Nazis marched into the Netherlands, Luxembourg and your home country.
So, essentially, it was faith in the League of Nations to negotiate Peace, Hitler initially seizing lands that identified as German, populations that supported appeasement and were in no mood for war, and tight economies that held those that could have kept Hitler in check from doing the right thing. And it's worth noting they absolutely thought they were doing the right thing at the time. Chamberlin didn't think he was being a pushover, he thought he was saving lives. It was a colossal failure of imagination.
If you need more info/clarification, let me know!