Each act of Siegfried moves in an upward curve from darkness to light, from a minor key and sinister orchestration towards a blaze of colour in the major. From the dominants of B flat and F minor to D and F-major in acts 1 and 2 respectively,a and from G minor to a glorious C major in the final act. …. No-one who has actually read Wagner’s writings and absorbed their basic idea can fail to sense in the smallest details as well as in the larger forms of the music in Siegfried an allegory of the movement from the “dark ages” to the bright light of the future.A movement from dark to light is well and good; but we might be forgiven for wondering what this movement means in more specific terms. Deathridge quotes W. himself: ‘Siegfried should not create the impression of a character drawn with the conscious intention of violating the standards of civilized society; everything he says and does—even the rather cruder aspects of his genuine boyishness—must be presented as the natural expression of an essentially heroic personality who has not yet found an object in life worthy of his superabundant strength. [quoted 62-3]
The same could be said, I suppose, of Fafnir: which is to say, he did find an object to which to devote his life (the gold); he just didn't find a worthy object. Similarly, Siegfried has an object—violence—just not a worthy one. W.'s too-much-protesting is significant, I suppose: because Siegfied does look like a problem He makes nothing and he keeps nothing; he only destroys. The former two activities are personified by Mime and Fafnir. What does that tell us about the priorities of Wagner’s worldbuilding?
Then there’s this, also quoted by Deathridge: ‘I was filled with proud joy’ (this is Hitler writing to Wagner’s son Siegfried) ‘I was filled with proud joy when I heard of the victory of the Volk—above all in the city where the sword of ideas with which we are fighting today was first forged by the Master.’ [quoted, 63]
Master means Wagner, of course; but if there’s one thing about which Siegfried is unambiguously clear it is that the person who forges the sword is not the person who fights with the sword. And maybe that's the disjunction at the heart of the opera: making and using.
It makes the opera look very twenty-first century. Because, if the big world-struggle in the C19th and C20th century was over the means of production, it's hard to deny the sense that today it is over the use of production ...