Who was the enemy?

But who was the enemy for the defenders if not some dark force – comprising the flutter of ghostly trepidation?

To quote one of the recently declassified documents from the vaults of the secret police:

The precise analogy is with an underground sect that seeks to undermine the very foundations of the wall… And yet we are forced to conclude: it is not just one sect we are dealing with but a proliferation of sects that splinter before our very eyes only to start up elsewhere.