I still occasionally see people on the Internet saying things along the line of "Jewish people control the media and/or the government". How has this idea persisted, considering its massive, poisonous (to say the least) effect on history? After the holocaust was revealed, how was this "idea" not thrown out alongside other "ideas" such as "Germany lost world war 1 because Jews stabbed them in the back"? Now, I did take a look for objective sense and came upon these links. I'd say they cherry picked the facts and it still doesn't provide proof of any of the aforesaid accusations of my kind.
Are you interested in a particular country or context in which this idea has persisted?
Because the answer in, say, the United States will be quite different than it is in, say, Iran, where anti-Semitism and these kinds of anti-semitic conspiracies have state-sanctioned support.
Actually the 'Dolchstoßlegende' is about the German army being stabbed in the back by the Social Democrats, a German Party (SPD), which advocated an end to the war. The 'International Judaism' was blamed for the loss of WW1 only as a result of the democratic parties being seen as controlled by 'the Jews'.