There was a temporality to the formation of that hard shell, the ancient city of Constantinople. An important detail that needs to be added to the analysis. What the inhabitants were finding in their growing desperation after the dramatic collapse of the Byzantine empire's holdings in the 7th century, and then the subsequent Arab sieges of Constantinople, was that they were literally standing upon the shoulders of giants: given the dramatically contracted state of the Byzantine empire, it would have been impossible to construct the Theodosian walls - among other things - with the available labor, talent, and resources at the time. The empire's citizens had to hold on tight to a possession forged over centuries of technological development and the concentration of resources, maintaining the fortifications and defensive technologies that existed prior to the sieges. Like a diamond formed under all that heat and pressure, it also took a good deal of time, and a broader spread of the circulation of resources, to concentrate all of that energy into one place. That fortress city and its clutched wealth was highly sought after by the empire's enemies, coming in waves to crack that oyster for the pearl inside.
