[johannes1234321]

In the past we even had space ships, which could start from ground, go to space, do stuff, come back and the could be reused. Having just a rocket isn't that much of an improvement.

That said: All the constraints on making it reusable and safe for humans are also a key factor why Space Shuttle was so expensive. With SpaceX's rockets not all parts need to resist the stress of reentry etc.

[KineticLensman]

> In the past we even had space ships, which could start from ground, go to space, do stuff, come back and the could be reused

The 're-used' aspect of the Shuttle involved massive re-fits which took months for each vehicle. It was like having to send your car back to the manufacturer for a total rebuild (often including engine change) every time you went for a drive. SpaceX is a massive improvement in this respect.

[jacquesm]

And two expended boosters and an expended fuel tank.

[HALtheWise]

Nitpick: the boosters were reused by parachute splashdown, but it was also really expensive due to (among other things) the corrosiveness of salt water. The External Tank was in fact expended.

[KineticLensman]

Each SRB consisted of 11 cylindrical steel sections. After flight and recovery, these were dismantled, refilled with solid rocket fuel as appropriate, and then reconnected to form a new SRB with all of the O-rings, etc.

So also a complete rebuild, with reuse occurring at the segment level, not of the whole booster assembly.

[Robotbeat]

Dragons are also reused (although at first, these newer ones will only be reused for cargo flights).

Additionally, SpaceX is serious about Starship/BFR. That's fully reusable and will be capable of going to the Moon (or even Mars) and back fully reusably: https://twitter.com/JaneidyEve/status/1102023437206388736