I would argue that a more "rational" and coherent program starting in the 1940s would focus not on pushing into service a weapon which people at the time quite rightly recognized was not particularly useful, but rather on developing the necessary underlying technology, such as large rocket engines, precise automatic guidance, storable and solid fuels, and so on, many of which would have useful applications in other areas in any case. Then, when the development cycle made ballistic missiles more practical, one or several could be developed with considerably less crash effort and expense, and probably with a longer service lifetime due to being more fit for purpose from the beginning rather than raiding bits and bobs of old German weapons for the underlying (engine) technology. Some people halfway grasped this, but a coherent development program was lacking, probably because of the Buck Rodgers factor.
Might have a point but I'd argue that it was both a failure to recognize future potential and a lack of incentive that hindered early development. Couple that with the post-WWII draw-downs, then Korea, followed by obvious Soviet progress and constant inter-service rivalry and you pretty much end up on the path that was taken. Change any element and/or the underlying situation and you may get a different outcome but I'm skeptical that any one factor is that critical.
I don't think storables were all that much of a killer for the Titan II. It served about as long as the contemporary solid missiles Minuteman I/II and Polaris, and was only retired as part of an ordinary military replacement cycle. Sure, once you work out big solids you probably aren't going to build a storable liquid missile, but if you have 'em they're probably not going to be replaced early over it, unlike the kerolox missiles that have too many operational disadvantages to have a long service lifetime.
Not a "killer" for the Titan II but the reason there was a Titan 1 first. Titan 1 had operational issues dealing with it's launch time cycle where as Titan II had operational issues related to it's propellants and maintenance life cycle. It wasn't actually replaced due to any military life cycle issues but due to its higher cost for maintenance and that was directly tied to it's propellants. A small example would be the hydraulic fluid used in the silos. This was standardized prior to the introduction of the Titan II and despite efforts to develop a fluid that would NOT react to the Titan II propellants none was ever found to be cost effective.
Liquid propellants where never very "cost effective" for the military which is why most missiles went to solids as soon as the tech matured, Storables were somewhat acceptable as interim solutions but overall were only marginally better than cyro-propellants and only because they were somewhat operationally "better" even if they were functionally inferior. (Which many were) One wonders what would have been the effect if the US hadn't been so biased against (and arguable worse at handling than the Germans who at least had the excuse of an on-going war to their credit
Unlike a spill of LOX or RP-1, Hydrazine and RFNA got your attention to get the hazmat crews on it, pronto, and was expensive to clean properly
The Synthetic rubber and perchlorate in the Solids, you just didn't have to worry about.
This as well
An interesting question here would be what would happen if someone other than Eisenhower was setting defense policy at the time, for instance if Dewey had won the 1948 election. Dewey was in the same general circles, so things probably wouldn't look too much different, but if there's less focus on massive retaliation as the answer...? Maybe IRBMs and ICBMs would be seen as a lower-priority program then (at least until Sputnik) and you might get a smaller number of programs out of it.
I highly suspect that "New Look" and massive retaliation that turned the Air Force into the primary service was very much a part of the equation. For the most part the "bomber generals" were very much dead set against ballistic missile development and it took a combination of Gardner and Schriever to ram a "compromise" development program through the Air Staff in the first place.
Dewey's appointments might have butterflied away Gardner and without that pressure... On the other hand if something happens to Schiever then there's no support (or very little) on the Air Staff to support missile development.
Then again, if missile and rocket development are slowed down you have even MORE pressure once the Sputnik-panic hits and the US starts out even further behind...
Although this is not a "What if the MX-774 wasn't cancelled?" or similar thread, that is what I think too. An additional benefit would probably be that they would be more reliable because they had more time to test the components. More reliable launchers would be very helpful in the early years of the space programme too.
Maybe? Because really there was a good amount of work done but the direction was spotty at best except for a few programs and support wavered a lot.
Reliability was variable even at the best of times and you really needed to push more than a few areas to get significant progress. For example the Viking sounding rocket of the NRL was a pretty reliable and effective launch vehicle but it was neither cheap nor easy to turn it into the first stage of the Vanguard LV. And in the end a more effective "solution" was using the Thor IRBM as a first stage leading to the Delta launch vehicle.
Conversely the Redstone tactical missile was robust and reliable and pretty easy to turn into the "Juno-1" launch vehicle when the tank was stretched and the motor upgraded. And it was very conservatively based on well understood developments of the V2 and eventually contributed to the Saturn-1 LV.
Different teams, different services, different levels of support and different outcomes...
Randy