"Is that not marginalization?"

YOU used the term "silence" to suggest the administration was trying to silence Fox News. Not exactly sure what you mean by "marginalization". If the idea is that the administration is suggesting Fox News has an agenda/anti-ideological posture which is seeping into its reporting of the news, I have no problem with that (surprise!), since I wholeheartedly agree that Fox is not acting as an independent news service. What Fox is doing, IMHO, is catering to its viewership, many of whom are avid listeners to the political commentary talking heads the network features (O'Reilly, Hannity, etc), by presenting its news in a fashion that compliments its commentators. You may of course disagree with this analysis, but the administration is within its rights to "marginalize" those who it perceives to be a biased and unobjective source of information.