There is little the Federal Communications Commission can say about Fox News or MSNBC since the channels are on cable, not delivered over the broadcast airwaves.
True, but don't rest too easy. The FCC has whatever authority that U.S. Congress gives it. It's been lobbying for explicit authority over cable and the Internet, and they'll get it if the public wants them to have it.
We have a chance to leave behind the bad old days where U.S. citizens are "protected" from seeing anything that D.C. folks would consider objectionable. Getting there requires that the FCC not regulate the new networks, and they really want to.