Pat Flannery wrote:

The trick is the timeframe...having the V-2 to serve as a example that a
large rocket was possible served as a major incentive to build them, and
I think things would have advanced slower without it.

I didn't have a "trick" in mind (and probably shouldn't have phrased
the question so much in alt.history.what-if style). It's really a
two-stage :-) question:

If no Peenemunde program and no V-2, how long for *scientific*
motivations and budgets to push us to sounding rockets a la Aerobee?

AND

If no prospect of nuclear warheads, how long for *scientific*
motivations and budgets to push us from something like Aerobee to
orbit, with Vanguard or the like? Or would a first commercial commsat
or first miltary spysat have done the trick?

In a way, it's a question about Big Science and the associated Big
Bleeding-Edge Engineering, which historians agree was very much a
legacy of WWII. After radar, jets, the V-2 and the A-bomb, scientists
who previously had thought $50K was big money had access to millions,
so we would stay ahead with wonder weapons (or at any rate not be
surprised by somebody else's wonder weapons). But to what extent would
the US or USSR have seen a high-explosive-only uber-V-2, antipodeal
bomber etc. as a wonder weapon worth pursuing?

I remember a "won't it be great?" IGY poster in my classroom in 1956,
and in hindsight I know that planning for it had been going on since
1952-1953. Would a satellite (rather then just a slew of up-and-down
instrument packages to the exosphere) have been part of the mix if the
scientists hadn't had the benefit of pedal-to-the-metal engineering
towards the R-7, Redstone, Atlas etc?