Let's just toss out all physics pre 2000 because it's old. lol. Truth doesn't age. Just using ITER as an example. I can update that link with a Commonwealth one in a few years I suppose.
Manufacturability is a function of a lot of things like parts, systems, interactions, size, mass, supply chain, transportability, etc. Generally speaking, more complex things are less manufacturable and they become manufacturable by simplification and reduction. As a kind of measure of manufacturability, look at the cost. Think about the most expensive piece of technology that is mass manufactured today. It's probably the 777 or 737 - so price tag on order <$100M. Big ships are on order $10Ms. Maybe military procurement goes into the $500M, but those are low quantity and generally failed programs.
So if it's more than $100M and much more complicated than a wide body aircraft, today's economy and technology level is probably not going to be able to mass manufacture it.
The size and complexity of these fusion systems is physically constrained by various factors many of which are physics limited. And even with the innovations they propose but have yet to prove out, the size and complexity is still too large to manufacture.
Regarding fusion's proliferation risk: "One of the best ways to produce material for atomic weapons would be to put common, natural uranium or thorium in the blanket of a D-T reactor, where the fusion neu- trons would soon transform it to weapons- grade material. And tritium, an unavoidable product of the reactor; is used in some hydro- gen bombs. In the early years, research on D-T fusion was classified precisely because it would provide a ready source of material for weapons."
The big point Lidsky was making was that, for general reasons, DT fusion reactors will have lousy volumetric power density, compared to fission reactors.
So in addition to the points you make there, let's look at ITER's power density. Dividing the gross fusion power of ITER by the reactor (not plasma) volume, it will be about 0.05 MW/m^3.
In contrast, the power density of a PWR (gross thermal power divided by the volume of the reactor vessel) is about 20 MW/m^3.
ITER is worse by a factor of 400. Lidsky was being generous to fusion reactors, compared to this. MIT's ARC concept is about 0.5 MW/m^3, also much worse.
Lidsky's point is still valid, 35 years later, because it was based on generic arguments. Pfirsch and Schmitter were making basically the same argument in Europe at the time. Had they all been listened to!
Yes. The only number I could find for a Uranium PWR core was 69MW/m^3. Lidsky said in 1983 that "the power density is only one-tenth as large" (fusion vs. fission) so I assume this is what he was talking about. I only wanted to compare apples to apples.
Obviously, additional equipment surrounding the core or plasma adds to the volume, but the major portion of the construction cost is the steam equipment and power generators which is the same cost and volume per MW for either technology (or for fossil fuel power plants for that matter.)
The major part of the cost of a fission plant is the non-nuclear part, but I don't think that would be true of a fusion plant.
In any case, if some parts are common, but the non-common parts are cheaper in a fission plant, fusion will be more expensive than fission -- and since fission has already lost in the market due to its cost, fusion would do likewise.
Manufacturability is a function of a lot of things like parts, systems, interactions, size, mass, supply chain, transportability, etc. Generally speaking, more complex things are less manufacturable and they become manufacturable by simplification and reduction. As a kind of measure of manufacturability, look at the cost. Think about the most expensive piece of technology that is mass manufactured today. It's probably the 777 or 737 - so price tag on order <$100M. Big ships are on order $10Ms. Maybe military procurement goes into the $500M, but those are low quantity and generally failed programs.
So if it's more than $100M and much more complicated than a wide body aircraft, today's economy and technology level is probably not going to be able to mass manufacture it.
The size and complexity of these fusion systems is physically constrained by various factors many of which are physics limited. And even with the innovations they propose but have yet to prove out, the size and complexity is still too large to manufacture.
Regarding fusion's proliferation risk: "One of the best ways to produce material for atomic weapons would be to put common, natural uranium or thorium in the blanket of a D-T reactor, where the fusion neu- trons would soon transform it to weapons- grade material. And tritium, an unavoidable product of the reactor; is used in some hydro- gen bombs. In the early years, research on D-T fusion was classified precisely because it would provide a ready source of material for weapons."