It's not that malicious people. News media attempts to tell you something you didnt already know. Boston was new news. violence in "poor America" is not new, we already know about that. throw a couple stories about car chases and drive-bys up on the wall each evening and you've pretty much exhausted the subject. Now, put up a new gun-control law and all of a sudden gun deaths is news again, since it relates to important "new" legistation being considered. If the news instead focused on improving society and educating people, they would cease to exist. There are other entities pursuing these loftier goals. News media just entertains and informs, with the former being slightly more important, by necessity.
And stop this silly notion of "holding our journalists to a higher standard". As long as journalists work for big media, and big media makes money based on how many people watch...Then the math is simple. The "standards" the journalist is held to is the "standards" of the average american TV audience.
I dont see so much politics, conspiracy, or dishonesty here as much as I see basic free market economics. As Americans get poorer, we get dumber and our media just reflects what we want to watch. I'm not saying poor people are dumb. I'm saying that for many Americans who must work very hard just to make ends meet, the most important thing a TV can do is take their mind off the bullshit for a while, entertain them and tell them who won the damn game.