1. Fox News
Worst Show: Fox and Friends
The other channels on this list are bad in the sense that they pass off cheap thrills or easy sentimentalism/exploitation as entertainment. The harm they do amounts to little more than minor sins (mostly).
But when a cable channel can poison the discourse of a nation, well, that's something special. When a channel achieves this with such a caustic mixture of smugness and vitriol, it's even more impressive. When they do all of this while passing off lies as truths and truths as lies, by deliberately deceiving and agitating viewers, that is an achievement worthy of the highest recognition.