It was discouraging last week when discredited conservatives, who failed spectacularly on U.S. policy in Iraq, were given a media platform to talk about U.S. policy in Iraq. Last week’s Sunday shows alone, featuring the likes of Paul Wolfowitz and Bill Kristol, led James Fallows to argue , “In the circumstances, they might have the decency to shut the hell up on this particular topic for a while. They helped create the disaster Iraqis and others are now dealing with. They have earned the right not to be listened to.”

And yet, these discredited voices remain ubiquitous. Kenneth Pollack, for example, was on CNN yesterday, presented to viewers as a credible expert. Elliott Abrams, who pleaded guilty to withholding information from Congress during the Iran-Contra scandal, and went on serve on the Bush/Cheney National Security Council as head of the Mideast bureau, had a lengthy piece in Politico yesterday describing President Obama as “the man who broke the Middle East.”

And then there was ABC’s “This Week,” which welcomed Dick Cheney for his third Sunday show appearance since March. It went about as expected, though I was struck by the failed former vice president’s response to some of his catastrophic errors of fact and judgment.

“With all due respect, Jon, I was a strong supporter then of going into Iraq, I’m a strong supporter now. Everybody knows what my position is. There’s nothing to be argued about there. “But if we spend our time debating what happened 11 or 12 years ago, we’re going to miss the threat that is growing and that we do face.”

In “Monty Python and the Holy Grail,” there’s a scene in which John Cleese’s Sir Lancelot, certain he’s doing the right thing in behalf of a damsel in distress, storms into a castle during a wedding party, indiscriminately slaughtering most of the guests with his sword. The castle owner, eager to curry favor with Lancelot, urges the survivors to let bygones be bygones.

“Let’s not bicker and argue about who killed whom,” he tells his few remaining guests.

Cheney’s rhetoric is similar in its own pathetic way. Sure, he failed miserably, helping launch a disastrous war under false pretenses, the consequences of which we’re still struggling with today, but let’s not bicker and argue about who lied to whom about a deadly and unnecessary catastrophe. Pesky niceties such as accountability, credibility, and responsibility just aren’t important at a time like this, the argument goes

The difference is, in Monty Python, it was funny.

In the same Sunday show appearance, ABC’s Jonathan Karl asked Cheney about his recent op-ed in which he argued that Obama is trying to deliberately undermine the United States’ global standing, effectively suggesting the president is guilty of treason.

“I don’t intend any disrespect for the president, but I fundamentally disagree with him,” Cheney said.

Of course. All Cheney did was accuse a war-time president in the middle of a crisis of wanting to hurt the country on purpose. Why would anyone think the failed former V.P. intended “disrespect”?

Nevertheless, the divisions within the Republican Party on foreign policy were also on display over the weekend. While Cheney was condemning the president who’s tried to clean up Cheney’s messes, Sen. Rand Paul (R-Ky.) was doing largely the opposite, arguing that it’s a mistake to point fingers at the White House.