Possibly, but it's not unique to SLS. People were jesting twenty years ago about the purpose of the Space Shuttle being just a vehicle to get to and from the ISS. And the purpose of the ISS? So that the Space Shuttle would have somewhere to go.
> And the purpose of the ISS? So that the Space Shuttle would have somewhere to go.
I don’t think this is accurate. ISS was conceived almost 10 years after the Shuttle started launching, and the U.S. obviously had space station ambitions even before the Shuttle was on the drawing board (Skylab).
Additionally the Soviets did the exact same, with Mir being launched prior to the Buran’s first test flight — heck Salyut 1 was launched in 1971.
ISS stems from Space Station Freedom[1], which itself has its roots in the the Space Transportation System's space station component[2]. The Space Shuttle was a part of the Space Transportation System and the only part to receive funding and see development.
Again, the Challenger disaster was 12 years prior to the launch of the first ISS module. ISS missions only flew 37 times, out of 135 total missions for the Shuttle.
I first heard the saying I think sometime around the loss of Colombia. Maybe before, maybe after. By the return to flight, it was most certainly more true than false. By that time the shuttles performed very few non-ISS flights. I think that Atlantis flew a service mission to Hubble, other than that I can't think of any other shuttle flights that didn't go to the space station.
Columbia was heavier than the other orbiters, so she was flying the non-ISS missions from about '98 until her demise. After that US satellites were launched on disposable, unmanned rockets like the Deltas and Atlas.
