Certainly, we just talked about suborbital flight in light of Yuri Gagarin’s achievement in the orbital realm, which I think was a mistake on Russia’s part at the time. Certainly, it was a huge geopolitical win for the USSR, and whether I think it was technical overreach at the time, it spurred the United States to loft their own orbital missions. I would term this next step in general lockstep with the initial operational plan for Outbound as Human Orbital Flight. (OPS.5)
There are many goals for getting humanity on an Outbound track, and to really do that, humans have to be a part of space travel. Orbital spaceflight is the real point where the human element is needed to claim a foothold. The OPS.4 Suborbital phase is meant to dip the metaphorical toe into the pond, but OPS.5 Orbital means taking a real swim. You have to let go of familiar Earthly physical and biological norms, and acknowledge the technical advancements needed to allow for that disengagement. Orbital spaceflight demands real adaptation just for survival, and beyond that hints at the things we need to know to be truly useful in space.
There are so many things to be considered in successfully crossing the threshold into a sustained spacefaring activity, of which the below is only a minor subset to consider:
Advanced Life Support
Powerful Propulsion and Control Systems
Improved Reentry Systems and Materials
Of course, the above very short list only addresses some of the needs of orbital spacecraft to merely exist, but a smart approach to such development is to also begin to anticipate the greater function for those spacecraft in Earth orbit. In the historical space race the goal was to use Earth orbit as a transitional stage to a further mission to the Moon. We were not overly focused on hanging around the planet and keeping our permanence there. Again, as with the rush to beat each other in a political race, a logical technical progression of human spaceflight development was set aside, this time on the American side.