So were the striking miners at the Battle of Blair Mountain not proletarian?

I don't think Sakai would consider the white miners to be proletarian (as opposed to bourgeoisie proletariat) in the framework he develops in this text. I believe he is making the distinction between euro-amerikan workers as bourgeoisie proletariat and other proletariat groups to draw attention to the structural advantage they had from the start, and how their privilege has been maintained in general. IIRC part of his thesis is that the white american worker has an unspoken agreement to be an obedient servant of capital in exchange for a place of privilege in the world. This exists separate from the actions of individuals or even large groups of individuals such as those at Blair Mountain.

Sakai starts chapter 5 by clarifying that this classification isn't a condemnation:

... Communists have never believed that the working class was some "holy," religious object that must be enshrined away from scientific investigation... The political consciousness and material class role of the masses of any given nation cannot be assumed from historic generalizations, but must be discovered by social investigation and scientific analysis.

Sakai is certainly critical of the euro-american settlers. I don't think the distinction is intended to say they (we?) are hopeless. I strongly agree that there are barriers to achieving class consciousness in colonized north america that are unique, and that can be better understood through the lens Sakai applies.

I took a super quick ctrl-f through the pdf and while the author doesn't specifically mention Blair Mountain by name, he does discuss UMW and activities in Appalachia.

Selected excerpts:

In the UMW we can examine tactical unity over a 90-year period in a major industry. The fundamental reality was that Afrikan miners and Euro-Amerikan miners had tactical unity, but different strategic interests.

...

While UMW welcomed Afrikan workers as unpaid organizers and militants, when a mining community in the North became organized very often the Afrikan "union brothers" were told to get out. At the 1921 UMW Pittsburgh District Convention an experienced Afrikan delegate, recalling how he and hundreds of other Afrikan miners had taken up rifles to join the union's "Armed Marches" in West Virginia, complained bitterly:

Those colored men from the state of West Virginia put their shoulders to the shoulders of white brothers, and our newspapers tell us that they have sacrificed their lives for this great movement.

I think it looks very embarrassing when a man would sacrifice his life for this movement, and after the victory is won then his brother would say: 'We need you no longer.' A livelihood belongs to every man and when you deprive me of it... you have almost committed murder to the whole entire race.

I believe this is referring to Blair Mountain, which occurred shortly before this meeting.

The author goes on to explain the mechanism by which the privileged position of the euro-amerikan was weaponized to break that unity:

In doing this [driving out the Afrikan worker] the imperialists were merely carrying out their general policy on colonial labor, restricting its role in strategic industries and reserving the best jobs for Euro-Amerikans in order to ensure the loyalty of settler society. When most coal mining jobs were brutal hand-loading of the coal while working in two foot high tunnels, there were many jobs for Afrikan labor. But as unionization and mechanization raised the wages and improved the work, it became "too good" for Afrikans, and the companies and the UMW started pushing Afrikans out.

Who exactly are these “independent, self-sustaining peasants” in today’s US? A small percentage of large farm owners?

I hope in reading the above it is clear that the author isn't suggesting that the specific privileges the euro-amerikans enjoyed in early colonization have remained materially unchanged. The book explores how it has changed over time, culminating in point 4 of the image in the OP.

Slightly off topic, but I read this article recently and I think a lot of the themes are shared: https://mronline.org/2026/10/08/gill-imperialism-then-and-now/ I wonder if, when presented this way, it's easier to understand what Sakai is trying to say.

How can wages be suppressed and the market grow at once? There is a paralysing contradiction between profits, the suppression of wages, and the need for a consuming class. This is what generates, time and again, problems of overaccumulation, overproduction, and what the Patnaiks call a threat to the value of money.

This contradiction is historically resolved through imperialism–not as the highest stage, but as the very foundation of capitalism. The capital-labour relation would never have consolidated without an imperialist base. What enables workers to be both exploited and to function as consumers is the ability to draw in cheap inputs from the colonies and the imperialist peripheries. In addition to capital and labour, there are categories of labour and resources outside the core that can be appropriated without accounting for their reproductive conditions. Prices are imposed on peasants in the colonies because they have lost sovereignty–what the Patnaiks call a “price-taking” category of labour. This is not workers and trade unions bargaining for wages; it is the imposition of prices through the denial of sovereignty.

This isn't explicitly stated but when I read this I thought about how workers in america resist solidarity with because it requires them to acknowledge that their comparative place of privilege only exists because of imperialism and that it is on the backs of colonized people. Achieving worker solidarity that overthrows imperialism means giving up that place of privilege. I'm not going to pretend that isn't scary to me, comrade. But I have to strive for it.

If you can start in agreement with the above (which it sounds like you do?) I think it's easier to see Sakai's connection to the position of privilege settler proletariats have in comparison to colonized workers outside of the US. I think adding in recognition that the labour of enslaved Afrikans was critical to the establishment of the US as a imperial power is natural.

I hope it's not seen as dismissive that I don't address the rest of your specific points because I believe you have misunderstood Sakai's thesis. It's been a few years since I read it as a whole and I'm honestly running on fumes so I think I did a disservice to the text. I believe a lot of the specific things you bring up are addressed in the text in shockingly similar language but I'm going to struggle to find them right now.