Except it turns out we don't actually believe them about being objective. Gallup reports that 55% of people polled have little or no trust in the media to be unbaised, to report the news "fully, accurately, and fairly."
The breakdown by party line is revealing.
Seventy-five percent of Republicans and conservatives say the media are too liberal. Democrats and liberals lean more toward saying the media are "just about right," at 57% and 42%, respectively.If Democratic party adherents and liberals believe the media is just about right, that probably means that what they read and hear in the news closely adheres to their worldview--it reinforces what they already think.
Of course liberals and Democrats also believe (at least the ones I know, and the ones I read) that they have a better perception of the real world, and would argue that the reason conservatives and Republicans don't trust the media is because conservatives and Republicans are misled or wrong about the real world, so when the media reports the truth of the real world it conflicts with the mistaken conservative/Republican perceptions, and therefore it's not that the media is biased (it's still objectively reporting the truth), it's that the conservative and Republican worldviews have skewed so far from reality that the truth looks like a lie to them.
But none of that really matters. What matters is that 55% of people polled in the US don't trust the media to tell the truth. They turn to other sources, sources that don't even pretend to be unbiased, such as bloggers and talk radio hosts. And confirmation bias works again to preclude a community that acknowledges difference and works toward compromise.
This breakdown in trust is a problem for the media to choose to address, or not. But as co-occupants of our society we need to build responsibility toward our community, to commit to shared goals, to lessen our burdens by working together, and I believe these tasks are much more difficult when we lack the insight into other people's thinking and opinions that is the natural consequence of living in the echo chamber.