One of the causes of the bias is that decision-makers in the media organizations preferentially hired those that shared their ideological commitment. This is ea

One of the causes of the bias is that decision-makers in the media organizations preferentially hired those that shared their ideological commitment. This is easier in fields where a worker cannot prevent his or her ideological commitment (or lack thereof) from showing in his or her work product. Besides journalism, other fields with this property are the social-science and humanities departments of universities, which is why those fields were captured by Leftist many decades ago whereas other fields were captured only much more recently. One department of the social sciences has resisted capture by Leftists, at least in the US, at least the last time I looked, namely economics. One could argue that that is because it was captured first by liberal or libertarian ideologues. This comment is restricted to the US and Britain because those are the only 2 societies I know well enough for my observations to have any value. Also, the OP is about American teenagers specifically.