There's the standard left-blogosphere explanation, which I think is pretty accurate: the media grant more credibility to Republicans in general and John McCain in particular on matters of foreign policy and terrorism. Obama's margin for error on these things with the press is razor-thin. McCain, meanwhile, can get basic world geography wrong and still get a pass. (For the record, I don't think McCain's verbal miscues merit a feeding frenzy -- nor should Obama's.)
This double standard is a deeply ingrained habit. It dates in its current form back to the 1980s, but really all the way back to Nixon. In the minds of the media, the principal political legacy of Nixon and Reagan, and to a lesser extent Bush 41 (who lost due to a sour economy), is the iron linkage between Republicans, an attitude of American "strength," a policy of interventionism abroad, and victory at the ballot box.
But during the past eight years, the practice of projecting "strength" in foreign policy changed. Instead of a single, rather amorphous feature of the president's foreign policy, "attitude" became nearly the whole damn thing.
Meanwhile, the quality of our foreign policy as policy -- that is, government decisions taken with some intelligible long-term strategy in mind, some understanding of the world, and some interagency coordination -- declined precipitously. Nixon, Reagan, and Bush 41 (and while we're at it, Ford, Carter, and Clinton) had their failings, but all ended up conducting foreign policies that look pretty good compared with what we've got now.
This is pretty obvious, and more an objective truth than any presumed correlation between bluster and winning elections. The public has recognized it: we're in a ditch. But in covering Obama and McCain, the media still behave as if the various strategic blunders of past eight years never happened. This requires making a value judgment, which the media can't, and won't, do. So it's very hard for them to credit Obama for foreign policy insight, even when -- especially when -- events align rather well with his policies.
The other driver here is fear. Political journalism is basically 25 percent facts and 75 percent interpretation and speculation. (Which is why it's stupid.) There is a great premium placed on seeming "out in front" of the pack in interpreting events -- but not too far out, in case the pack starts moving in a different direction. And in terms of crowd dynamics, traditional media outlets revere nothing more than their sometime foes in the conservative media. Drudge, Fox, Rush Limbaugh and the rest have the ability to spontaneously (or not-so spontaneously) align on a particular topic, creating the illusion of a populist wave. The MSM bought the Karl Rove view, mistaking this narrow intensity for broad, popular sentiment. They envy it. Consciously or not, they hew to its conventions. To give Obama too much credit on foreign policy risks a mocking, pseudo-popular backlash from the conservative media -- based on some minor Obama gaffe, say (as Jon Stewart so artfully lampooned last night) - that spills over into the mainstream.
It's all the stranger because what's coming out of Iraq is great news not just for Obama, but for the United States. Look at the Bush administration's ridiculous fumbling over Maliki's statements. Take Obama out of the picture: from the standpoint of U.S. Iraq policy, this is a very positive development. Things are stabilizing to the point where we can talk about withdrawal. Bush did something right! Holy crap! But the White House is so heavily invested in ... making Obama look bad? Military bases forever? ... that it cannot acknowledge even its own apparent success. In other words, the stated aims of U.S. policy and the actual aims are not the same, and the contradiction is tying us in knots. Alas, the media haven't noticed this obvious tension either.