[snrplfth]

One big obstacle to established players was the fact that a lot of existing booster stages had been optimized in such a way that they simply could not survive atmospheric reentry, lateral stress, and could not land. Both major operational US rockets, Delta IV and Atlas V, have exterior insulation (which would burn away upon reentry), relatively thin walls (meaning they're not very strong against aerodynamic buffeting or fin torque), and single engines (meaning that it's very hard to throttle down to land). Adapting these rockets for reusability testing would have meant basically redesigning them from the ground up.

[ufmace]

Probably more importantly, the idea of landing a rocket was basically impossible until computer control got good enough to handle the descent and landing.

[snrplfth]

For sure - but it's been good enough for a while. Consider the McDonnell Douglas DC-X in 1993: https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X

[greglindahl]

DC-XA set a height record of 10,000 feet, and pretty much goes straight up and down. So it proved out most of what Blue Origin's suborbital rocket does, and the last part of what SpaceX's first stage does, but not the re-entry burn and flying a cylinder stuff.

[_0w8t]

Soviet space shuttle Buran landed automatically from space in 1988 using Soviet-made hardware and software. So I very much doubt that using recent computer chips were essential to land the rocket.

[imron]

> Adapting these rockets for reusability testing would have meant basically redesigning them from the ground up.

And now they're going to have to do that anyway if they want to compete with SpaceX, so what the GP said is true, it's something established players should have done a long time ago, and they're going to be noncompetitive for a period of time as a result.

[snrplfth]

Correct - they just went down the wrong optimization road, so the incremental development program for Falcon 9 landing is nothing they could have replicated.