User blog comment:Hawki/Nova Covert Ops, part 1 - Reflections/@comment-72.197.211.140-20160613231731

PsiSeveredHead, it's hard to know if the Psi Disruptor was a major secret or not. In order to know if a lot of military people know it or not, it'll depend on how well the Confederacy had known of the effects of the Psi Emitters. SC1 seemed to imply that the Confederacy knew the emitters lure in Zerg, but they didn't expect it to lure in THAT many. This implies either the Confederacy completely underestimated the emitter's potential, or they had no clue how numerous the swarm really was.

Obviously, if it's the latter, then it'd make sense for them to make a desperate scramble to build the Psi Disruptor in order to ensure the Zerg won't be as effective on the battlefield. It'd also explain why only ONE disruptor was built, as perhaps they found out about all this too late in the day.