… Morally grounded opposition to subordination, exclusion, and deprivation, perhaps best seen as linked by a concern for the vulnerable, defines what I am inclined to argue is the minimum core of a leftist position. I do not mean to suggest that all those who might claim to be leftists would acknowledge just these commitments—the Stalinist or the Maoist seems unlikely to exhibit much in the way of concern for the particular vulnerable person. And I do not mean to deny that many of those associated with the left might go on to hold particular positions about the most effective or just ways of achieving leftist goals. Some might argue, for instance, that a position was not authentically leftist if it failed to involve recourse to the state or the use of physical force against persons to prevent subordination, exclusion, or deprivation. This seems to me to be a possible development of leftism, but not a necessary one. There is, at minimum, no reason why someone who supports the anarchist project of doing without state could not adopt a leftist position of the kind I have described.
I think it is clear that a market anarchist could be a leftist. Whether a market anarchist should be a leftist is, of course, another matter. Whether she should be will depend on what reasons warrant opposition to subordination, exclusion, and deprivation, and the consonance of those reasons with her reasons for endorsing market anarchism.