Alright, instead of looking at just one article, here's my running list (from 20 minutes of clicking around on the old reliable sites) of conservatives that are currently running the same argument, which proceeds along the following lines:  The liberals say that conservative rhetorical invective is wrong. That's hogwash, because they do it too.   Here's the cattle call:

The editors at NationalReviewOnline see the hypocrisy in the accusation itself:

The irony of criticizing the overheated rhetoric of your opponents at the same time you call them accomplices to murder apparently was lost on these people, most of whom have never been noted for their subtlety (or civility)

Roger Kimball sees the tendencies on both sides, but the Liberals have it worse:

At one you are likely to see signs decrying socialism, big government, Obamacare, high taxes, etc. At the other you are likely to see signs advising you that “Bush = Hitler,” proclaiming the imperative “F*** Bush,” etc. Really, it is instructive to compare the rhetorical temperature, and general drift, of the two sides. One complains about various policies.  The other complains about “a culture of hate” while at the same time wallowing in it.

David Limbaugh at TownHall.com can't help but 'put aside' noting the hypocrisy of the lefties to wag their finger about tone:

Let's put aside, for now, the unhinged left's ongoing violent rhetoric and imagery against former President George W. Bush, Palin, conservative talkers and others on the right. Let's put aside that if certain rhetoric causes violence, then liberals' false depictions of Palin as advocating violence or their fraudulently smearing Rush Limbaugh as a racist based on manufactured stories could lead to violence.

Rachel Alexander at TownHall.com finds a case where a Democrat also used actual gun-imagery for electoral purposes:

[T]he left ignores the fact that one of their own, defeated Arizona Democrat Congressman Harry Mitchell, ran a campaign ad against JD Hayworth in 2006 featuring Hayworth in the crosshairs of a rifle.

Mona Charen, also at TownHall, notes that the media failed to blame Liberal opposition to Regan for the assassination attempt on him:

Ronald Reagan was nearly killed by a similarly mentally ill gunman. Did anyone suggest that liberals or Democrats encouraged or inspired John Hinckley?

Cal Thomas totally misses the point, and he just reverts to interpreting every criticism as an expression of dictatorships:

Long before modern media, newspapers condemned politicians they didn't like, questioning their character and moral fiber. To end vibrant, even incendiary political rhetoric, would require the eradication of politics, itself. Other countries have such a system. They're called dictatorships.

Um, wait, that's not chastising someone for not toning down their rhetoric, too… that's ramping up the rhetoric when someone says you should tone it down.  Wow.  Is Thomas always more angry than sad about things?  OK, so not a tu quoque, but weird. Just weird.

Stephanie Hermann (of Right Grrrrl) has a post over at American Spectator, titled, "I've Got Your 'Inflammatory Rhetoric' Right Here…", which is composed of a long list of mean things said by people who pass for liberals.

Jeffrey Lord, also at American Spectator, quotes  "one very angry federal judge," who "declined to be cited by name:" 

[H]ow ironic that the one constitutional officer to die was a conservative, Republican-appointed federal judge. Will anyone point out the hypocrisy of liberal media on that one?

I'll end with Ross Douthat, who marks the hypocrisy, but makes what I think is a sensible distinction:

But if overheated rhetoric and martial imagery really led inexorably to murder, then both parties would belong in the dock. (It took conservative bloggers about five minutes to come up with Democratic campaign materials that employed targets and crosshairs against Republican politicians.) When our politicians and media loudmouths act like fools and zealots, they should be held responsible for being fools and zealots. They shouldn’t be held responsible for the darkness that always waits to swallow up the unstable and the lost.