Although Spencer coined the term “alt.right,” many who describe themselves as alt.right are more in line with paleoconservatism — that is, the American nationalism espoused by folks like Pat Buchanan.
But Spencer and similar white identity thinkers are the antithesis of the so-called social justice movement (of which ThinkProgress is an example.) The SJ is a collectivist movement which classifies people into groups, each member of which is assumed to be personally affected by every wrong or oppression affected by members of that group at any time in history. And, per SJW dogma, white people in general are the oppressors. Of course, when the oppressed are women, the historic oppressor is white men. If the oppressed were LGBT, the oppressor is straight white men — each and every one of them.
White identity is a complex way for whites to say “Hey, wait a minute! Why are all those other groups allowed to assert their identities against us, but we aren’t allowed to claim our own European heritage and organize ourselves in our own interest ?”
IOW, it’s a mirror of the racialist left.
The logical outcome is true multiculturalism; that is, the organization of American society into gender, ethnic, and racial collectives that are generally hostile to each other.
IOW, an SJW utopia.