Yes . . . I first noticed it growing on the Left at some point after G.W. Bush took office and then saw it get actively expressed during Barack Obama's interactions -- or blatant lack thereof -- with Netanyahu after the Left's sacred Anointed One became president.
At that point when Barack sort of gave leftists a green light it started being much easier to detect the no longer quite so subtle anti-Jewish strain running through the upper level hierarchy of the Dem Party's leadership and their elites.