What gets shown on the news is what people watch. If the ratings and focus groups show that people are no longer interested in certain things they switch to something that will keep viewers watching.
There is no news organization on cable that isn't there to make a profit. It really has nothing to do with liberal or conservative it is about what gets viewers like you to watch so that the people that advertise on the networks will pay for airtime.
So you see, it is now and always has been about what makes money.
Hmmm, I wonder. Maybe it's because our soldiers are not allowed to fire without specific instructions and prisoners get Mirandized? Afghanistan, the kinder, gentler war.