It's Nick Szabo. He uses his initials for his Pseudonyms (N.S) Nakamoto Satoshi = Bitcoin Nicolas Saberhagen = Monero
Szabo later went on to improve on the concept with Monero, without the involvement of US Intelligence (obviously, since Monero is very unfriendly for the US Govt). Again, speculation. The only person capable of creating both, is likely Szabo. Monero being a big middle finger to "the team" behind Bitcoin, who still control the keys.