I think when Reagan fired all the ATCs, they were temporarily replaced with military trained ones until they could hire and train replacements. But that was a time when there was significantly less air travel and less ATCs than we have and need now.
So maybe they might have the military take over some positions? There's no way they could fill every single airport and I doubt that they even have the same training and skill set as commercial ATCs.
But having a military take over of airports is the kind of dictator move that probably makes someone like trump salivate.
Interesting those numbers have largely not changed in 40 years. Honestly I was guessing that we needed way more ATCs since the strike because air traffic has increased so much since then. Do you happen to know why the need for ATCs hasn't really changed?