Would it be harder legally to "want to conscript all people (men and women)"? What I mean is even though women are not registered for selective service, if you were to "enable" conscription couldn't you just also require that they register? If this is the case isn't it fair to say instead of "men are subject to involuntary draft" it is more accurate to say "men are one record-keeping action closer to an involuntary draft"?

If there's a bigger difference I'd like to understand that difference.