Existing Commercial Potential for Helium-3 from Luna

> But delta-V is not the problem, because solar sail propulsion could
deliver already unlimited delta-V
> while ion-propulsion delivers also much better delta-V than
conventional. The long acceleration time
> (low thrust) is the problem now.
>

Non-sequitur.

Solar sail and ion propulsion can also be used to get to the Moon.
Tethers can also be used.

There is no silver bullet here. The choice of propulsion depends
how quickly you want the return on the investment, i.e. how long the
investors are willing to wait.

Today, that drives all commercial missions to use rockets and higher
acceleration.

Consider this, Frank, why do commercial comm-sats today always use
chemical rockets?

They could save a lot of launch cost using ion rockets or solar sails
to get into Geosynchronous orbit. The reason:- The investors are
more interested in getting the bird on station as quickly as possible
so they can start top get the revenue stream as quickly as possible.
A dollar today is worth much more than a dollar next year.

Lunar missions can deliver return much more quickly than asteroid
missions, that will interest investor who want fast ROI.

Investors are not especially interested in cool technology nor fancy
rocket ships, they just want their profit as quickly as possible. If
Buck Rogers can bring home the bacon faster than the competition,
then you will get the money. Otherwise, dream on.

As a practical matter, that is how it works in the space business,
and business in general.

Time is money.

That is not to say investors never perform long term planning, but
they need to see risk reduction and feasibility before committing
funds for the long haul.

Indeed, that is where the synergy of lunar-asteroid development comes
in.

Rapid response lunar companies can validate the business models, to
give investors the confidence to invest in more long asteroid type
missions.

A case in point is the Clementine mission. It was designed to
visit both the Moon and an asteroid. It visited the Moon first,
because it is closer, and allowed the spacecraft to be fully checked
out prior to going to the asteroid. As it turned out it failed
before it reached the target asteroid.

Frank I read your long email were you have written a long grand
description of a large scale elaborate solar system development
infrastructure. But it contains a lot of unknowns and new technology
developments, with a lot of technical and financial risk.

It may well be a good idea in the long term.

But no investor is going to take all of that on faith.

Investors want to see demonstrations; investors invest in a track
record of success. They do not (usually) invest in vaporware.

If you really want to see solar system development, you will have to
demonstrate feasibility to investors via deploying technology
demonstrators in the lunar environment.