Phibian on the Fall of Constantinople

In honor of the EU election today in France, Phibian, at CDR Salamander, has a long, really interesting post about the Fall of Constantinople on this day in 1453. It's a devastating story of a city state caught in Islam's headlong expansionist rush. Also, if memory serves me correctly, the reason it happened, ultimately, was that other Christian European nations, engaged in their endless power plays, refused to send help when help was needed.