Using the Wikipedia definition, white nationalism is:
White nationalism is a type of nationalism or pan-nationalism which holds the belief that white people are a race and seeks to develop and maintain a white national identity Its proponents identify with and are attached to the concept of a white nation. White nationalists seek to ensure the survival of the white race, and the cultures of historically white states.
Relatively benign, though the definition continues to a more malignant form:
They hold that white people should maintain their majority in majority-white countries, maintain their political and economic dominance, and that their cultures should be foremost. Many white nationalists believe that miscegenation, multiculturalism, immigration of nonwhites and low birth rates among whites are threatening the white race, and some argue that it amounts to white genocide.
Viewed analogously passive white nationalism could be compared to the actions and interests of the NAACP, while white supremacy can be compared to the militant strands of the Black Panthers or the Black Power Revolution.
From that, if viewed as a venn diagram, are there any notable white nationalists that aren't white supremacists?
Clarifying the Scope of the question:
White Nationalism is actions or beliefs aligning with the first quote block, while White Supremacy is the first amplified by the second quote block. The goal is to find a notable representation of someone that celebrates being white and the continuation of white people, without a mandate for dominance, racial supremacy, or subjugation of non-whites.
Further, while the existence of one notable representative of white nationalism with out a mandate for supremacy is sufficient to answer the question, any claims that an example doesn't exist will be significantly burdened with the task of proving the existence of a representative is impossible.
Analogy Validation Is the concept of benign white nationalism comparable to the NAACP? In a review of the Wikipedia definition for Black Nationalism, the NAACP is specifically highlighted, citing that:
The NAACP is a civil rights movement inspired organization aimed to fight prejudice, racist, Jim-Crowism related segregation. The organization is intended to benefit all those victims of the above mentioned specifically "Colored people."
From the same reference, Malcolm X could be cited as a notable Black Nationalist, especially after his pilgrimage to Mecca.
Intent Assuming that every white nationalist is a white supremacist/separatist, because of understood colloquialisms, establishes an unsubstantiated tautology. This exasperates the permissive environment in which hatred, animosity, and violence can be justified, once the target has been labeled "Nazi." This question deigns to drive a proof by contradiction, or to invalidate the premise
Proof by Contradiction A = White Nationalist B = White Supremacist/Separatist
Start with the proposition where B is a proper subset of A (the opposite of our expected result), where it is assumed that there exists a value in A that doesn't exist in B. If it can be proven that every value in A is also exists in B, then B is not a proper subset of A, establishing a proof by contradiction; ergo A=B. However, if a value can be identified that exists in A, but doesn't exist in B, then the proposition is proven