Quite right of course, Warmtoast. My suspicion though is that we obligated ourselves to Poland because its invasion would constitute a line in the sand crossed that meant that Hitler was on a roll and thus posed a direct threat to us.
The Saarland, Austria, The Sudetenland, had all been gobbled up on the specious pretence that as their inhabitants spoke German they hence belonged within the Third Reich, whether they wished it or no. Poland was obviously an exception to any such rule despite Danzig, as was of course the previous seizing of the remainder of Czechoslovakia.
Funny how that all strikes a bit of a chord with present day events isn't it? Particularly ironic is a German Chancellor reporting to a Munich conference that a military confrontation with another dictator, bent on a similar gathering in of the Herrenvolk, was not the answer but that negotiations should produce peace in our time! What goes around comes around...