No it isn't, it's been done periodically for certain groups since World War II. The DOJ published lists of groups designated under E.O. 9835 and 10540 during the Cold War.
The US Congress published a long listing of extremist groups (pro-Nazi, pro-Japanese imperialism, White racist, communist, etc).in their “Guide to Subversive Organizations and Publications (and Appendixes), original version Jan. 2, 1957; Revised and published Dec. 1, 1961.
There was, in Appendix I, “Organizations Designated by the United States Attorney General as being Fascist or Otherwise Extremist in Character”. Included on this list of Japanese extremist groups were, under “Fascist Organizations” were the pro-Germany/Nazi organizations, while under “Organizations Which Have “Adopted a Policy of Advocating or Approving the Commission of Acts of Force and Violence to Deny Others Their Rights Under the Constitution of the United States”:
“American Christian Nationalist Party”
“Associated Klans of America”
“Association of Georgia Klands”
“Columbians”
“Knights of the White Carmellia”
“Ku Klux Klan”
“Original Southern Klans, Inc.”
“Protestant War Veterans of the United States, Inc.”
“Silver Shirt Legion of America”.
Most went out of existence during WW2, changed their names, or merged with the KKK’s major organization. A few may have become known as “The Citizens Committee for ....”
There was also the “Attorney General’s List of Subversive organizations” which the Democrats, through the courts, had abolished in the 1970’s.