"The Hydrogen fad is why the Shuttle had SRBs (because the SSMEs couldn't generate enough thrust on their own to get off the pad)..." Errr, not to my memory.

"The Hydrogen fad is why the Shuttle had SRBs (because the SSMEs couldn't generate enough thrust on their own to get off the pad)..." Errr, not to my memory. Back when it was being thought about, Single Stage To Orbit (SSTO, https://en.wikipedia.org/wiki/Single-stage-to-orbit https://en.wikipedia.org/wiki/Single-stage-to-orbit) was beyond the foreseeable state of the art, and the initial plans were to have to complete, reusable stages, a 1st stage big monster that would get the 2nd stage high and fast enough, and then would land "normally". But NASA just didn't get enough money to do it right (the '70s were a particularly bad time to be trying to do such a thing in the US, and in things like the SSMEs just plain screwed up (https://news.ycombinator.com/item?id=7711061 https://news.ycombinator.com/item?id=7711061). So at practically every turn, they sacrificed true reusability, operating costs, and ultimately safety (not a coherent design, but a series of compromises, and of course no provision for failure) to keep development costs within their budget.