First let me state for the record and very sincerely, I oppose any violent organization, or segregation/superiority, regardless of who the groups are. So that includes the aggressive KKK  but also equally includes Antifa and the BLM and so on. If constraints are in place, good. They need to be.

"Unite the White" (The rally folks) consider the KKK, or the Knights to be the White Resistance, and/or White Lives Matter. Both identifications are fair enough as we see the same with different races and their organizations. It just causes a internal cringe as we are so accustomed to hearing the word White in conjunction with privilege, with a sense of entitlement.

You can read the 'Unite the White' National Socialist Movement statement here. 
http://www.nsm88.org/reports/UniteTheRight_Aug_2017_afteractionreport.htm