Czechoslovakia's border mountains, forts, artillery, and tanks would make a 1938 German attack costly. Poland would have an opportunity to mobilize, and France could advance while the German Army was less developed than it became in 1939. Germany would also lack access to Czech factories and military facilities. Those resources mattered to its later preparations, so an earlier war would change both the initial fighting and Germany's industrial position.
Notable Point · 52:57-53:35
Czech defences and industry in a 1938 war
A 1938 war would confront Germany with fortified Czech mountain borders while denying it the factories acquired after Munich.