The month of April saw some dark days for America. On April 19, 1995, it was the Oklahoma City Bombing. On April 15, 2013, it was the Boston marathon bombing. What do those two have in common? Liberal media outlets smeared conservatives as responsible for both.

On the April 19, 2010 edition of Countdown, then-MSNBC host Keith Olbermann went on an unhinged rant, assigning Rush Limbaugh culpability for the actions of domestic terrorist Timothy McVeigh:

What was the more likely cause of the Oklahoma City Bombing [that killed 168 people]: talk radio or Janet Reno’s hands on management of Waco, the Branch Davidian compound?... Obviously the answer is talk radio. Specifically Rush Limbaugh’s hate radio…. This is an exact parallel to the paranoia that Limbaugh stokes daily among those who feel themselves invaded by the U.S. government today. Limbaugh claimed others would have blood on their hands in the event of future right-wing terrorism. Frankly, Rush, you have that blood on your hands now and you have had it for 15 years.

On the April 16, 2013 edition of All Things Considered, NPR reporter Dina Temple-Raston admitted that she didn’t have the facts about who was behind the Boston Bombing:

Well, officials told us that they have some promising leads, though no actual smoking gun. They expect this case will take weeks, not months, to solve. The thinking, as we've been reporting, is that this is a domestic extremist attack. And officials are leaning that way largely because of the timing of the attack.

But, of course, that didn’t stop her from speculating. Temple-Raston heavily hinted that “right wing” types could be behind the attack:

April is a big month for anti-government, and right wing, individuals. There's the Columbine anniversary. There's Hitler's birthday. There's the Oklahoma City bombing. There's the assault on the Branch Davidian compound in Waco. And the FBI right now is comparing this to the Eric Rudolph case.

Because when you think conservatives, you think Hitler and Columbine, right? Of course, the right wasn't responsible. Radical Muslim terrorists were. But one of the first impulses for liberal journalists is to blame conservatives for terror. After the shooting of Congresswoman Gabby Giffords in 2011, New York Times columnist Paul Krugman slimed Limbaugh, Sarah Palin and conservatives in general. This type of smearing is nasty and appalling, but not at all uncommon.

For more examples from our NewsBusters Time Machine series, go here.