Margaret Soltan at University Diaries puts up a picture of her father-in-law, a cavalry officer in the Polish Army on the eve of WWII.
The picture can stand for many things, but it reminds me how long it takes to make changes. Yes, there were cavalry fights in WWI, but very few and none significant (unless you count camel cavalry and T.E. Lawrence). But here, 21 years later, a whole generation, a sovereign nation with brains and know how is still putting cavalry in the field. (As a side note, the Poles you remember were the ones who originally figured out the German Enigma machines, enabling Ultra to become a decisive factor in beating Hitler. ) Of course, the German Wehrmacht still moved by horsepower, but I don't think they had cavalry.