Jewlicious currently has a good post, "Israel Firster: The White Supremacist Roots," which discusses the fact that current far-left Israel-bashing uses the term "Israel Firster," implying the dual-loyalty canard. Who originated this rhetoric? Evidently one can find examples in Willis Carto's Neo-Nazi Spotlight newspaper, which stopped publication in 2001 according to the Jewlicious post and which I once became familiar with as part of some research into anti-Semitism.
I would add some other accusations and patterns that have now apparently attained some respectability on the left that one used to find only in the literature of Neo-Nazis and other anti-Semitic extremists. One is dwelling on the U.S.S. Liberty incident. Another is attacking the holiday of Purim. Another is sneering references to the "chosen people." And all this is without bringing up the subject of Gilad Atzmon.