“...he also proposed a Middle Sea Alliance between the Central European states as a bulwark against the Germans and the Russians.”
That’s still a great idea! One I’ve entertained, too. Beats NATO all hollow. Ukraine and Poland could lead the way, the former as a charter member of a group less troublesome vis a vis Russia, and Poland as a defector, in order to attract other eastern European states.
But Konrad Heiden was no lightweight. He would have some basis for his characterization of Pilsudski. Got to get ahold of a new copy, since my old, torn-apart one is long gone. But I recall it was annotated.
If anything, it was Roman Dmowski, who was Pilsudski’s political rival, that could have been more of a “Fascist”, as he was more of the “Poland for Poles” type. Pilsudski was actually a Polonized Lithuanian, who advocated a Multi-Cultural Poland, incorporating the Jewish and Ukrainian minorities in Poland.
I think NATO should break up into several European run alliances. Your description of Pilsudski’s proposed Middle Europe alliance makes all the sense in the world. The US could just be an ‘observer’ affiliate or not. Let there be a true Atlantic alliance with the US as the big dog in it or not. With the Middle European alliance it carries no past NATO baggage. One could very honestly say ‘Whats your problem Russia it isn’t NATO and it’s purely defensive!’. Of course unlike NATO it shouldn’t be used for expeditions like in the Balkan, the Med, etc.