[stripes1776]

How good could the Byzantine “national security” have been? They got trashed by Arab desert nomads bewitched by Muhammad.

By 1453 Byzantium was a small country in the Balkan peninsula engaging in a grand courtly delusion that if was still a great world empire, a bit like Italy under Mussolini in the 1930s.

[rmlew]

The Byzantines did pretty well until the battle of Manzikert where they held the Seljulks at a draw, but then retreated in civil war. It was political infighting that killed the Eastern Roman Empire.