NSA handles crypto, certainly (though even that is being pushed ahead by NIST), but the Navy already has been developing software (or overseeing its development

NSA handles crypto, certainly (though even that is being pushed ahead by NIST), but the Navy already has been developing software (or overseeing its development) for decades. They named a ship after Admiral Grace Murray Hopper, after all, and even today their Virginia-class SSNs already use Linux in some areas.