Anything that needs an air breathing propulsion system cannot be called a “space vehicle” of any magnitude. If it’s breathing air, it’s still in the atmosphere!!!
I will agree with that. I am not canceling the idea that air breathing can’t transition to something else at some point in the flight plan though. Ideally, that’s were we need to head if we are truly going to have a space plane. I’m not in the field, so take that with a grain of salt. I think you already knew that though. Hope things are going good for you.