I have to say this is a pretty good argument...
...However I have to add one thing; we live in a Republic, which means politicians cater towards what they perceive to be the people's wishes in order to get into power. Although Jewish media moguls have definitely been a major corrupting influence on society, their negative impact is only possible because of the people's gullibility, the Statism of WWI and WWII, and over time the trend towards degeneracy that has risen with the multitude of plagues such as feminism, abuse of the progeny, etc. etc.
While they're definitely not helping, some prominent ones (like Rand and Rothbart, and Milton Friedman if he's Jewish I don't know but I wouldn't be surprised) have made noble efforts to reverse the trends. The cancer of modern society arises from many roots, with Statism and Republicanism at the root of it. As degeneracy becomes more popular politicians will continue to issue degenerate and suicidal policies to maintain power in the here and now, leading to more degeneracy and so and so forth. The voter is as much to blame as the government since it is theoretically based on popular will. Of course in reality it does what it pleases within whatever confines it can get away with. However the collective body of voters affect greatly those confines...
So, to some up, our doom comes not from the Jews per se--the bad ones are simply exploiting it or products of it, not unlike the other races but they happen to be genetically superior to most and therefore over-represented--but the collective cancers our societies have come upon as a result of both republicanism and statism in general.