When a leading presidential candidate betrays a troubling ignorance of basic facts on the subject that he’s made the centerpiece of his campaign, you’d expect the press to sit up and take notice.

Today, The Washington Post did. In a blog post headlined, “A McCain gaffe in Jordan,” Cameron Barr and Michael Shear write:

Speaking to reporters in Amman, the Jordanian capital, McCain said he and two Senate colleagues traveling with him continue to be concerned about Iranian operatives “taking al-Qaeda into Iran, training them and sending them back.” Pressed to elaborate, McCain said it was “common knowledge and has been reported in the media that al-Qaeda is going back into Iran and receiving training and are coming back into Iraq from Iran, that’s well known. And it’s unfortunate.” A few moments later, Sen. Joseph Lieberman, standing just behind McCain, stepped forward and whispered in the presidential candidate’s ear. McCain then said: “I’m sorry, the Iranians are training extremists, not al-Qaeda.” The mistake threatened to undermine McCain’s argument that his decades of foreign policy experience make him the natural choice to lead a country at war with terrorists. In recent days, McCain has repeatedly said his intimate knowledge of foreign policy make him the best equipped to answer a phone ringing in the White House late at night.

Note only did the Post reporters make McCain’s embarrassing mistake the lede of their write-up, they also explained, in that last paragraph, why it matters in the context of the campaign.

That shouldn’t be surprising, but frankly, it is. That’s because the press often seems to take McCain’s national-security credentials for granted, without asking what those credentials consist of, or how nuanced and detailed McCain’s thinking on foreign policy really is. For instance, during the campaign, McCain has criticized the Bush administration for having led people to believe that winning in Iraq would be easy, despite having repeatedly said the same thing himself before the war. The press has barely taken note of the contradiction.

Indeed, this Associated Press story on today’s press conference makes no mention of the fact that the man who wants to be in charge of the war effort appears not to be familiar with some crucial facts.

So, will the rest of the media pick up on the Post’s report? We’re not holding our breath.