We have to define "liberal". The media is indeed generally liberal on social issues like civil rights and gay rights. But they tend to be quite conservative on economic and war and peace issues.
The media overwhelmingly supported the Iraq war until things began to go sour there. They also generally support globalization which helps the upper classes at the expense of lower wages and benefits for working class and lower middle class Americans.
“The things that will destroy us are: politics without principle; pleasure without conscience; wealth without work; knowledge without character; business without morality; science without humanity; and worship without sacrifice.” Mahatma Gandhi