For me, Mr. Obama showed signs of jumping the shark two weeks back, when he appeared at a podium affixed with his own pompous faux-presidential seal. It could have been a Pixar sight gag. In fact, it is a gag in “Wall-E,” where, in a flashback, we see that the original do-nothing chief executive of Buy N Large (prone to pronouncements like “stay the course”) boasted his own ersatz presidential podium.

For all the hyperventilation on the left about Mr. Obama’s rush to the center  some warranted, some not  what’s more alarming is how small-bore and defensive his campaign has become. Whether he’s reaffirming his long-held belief in faith-based programs or fudging his core convictions about government snooping, he is drifting away from the leadership he promised and into the focus-group-tested calculation patented by Mark Penn in his disastrous campaign for Hillary Clinton. Mr. Obama’s Wednesday address calling for renewed public service is unassailable in principle but inadequate to the daunting size of the serious American crisis at hand. The speech could have been  and has been  delivered by any candidate of either party in any election year since 1960.

What Mr. Obama has going for him during this tailspin is that his opponent seems mortifyingly out-to-lunch. Mr. McCain is a man who aspires to lead the largest economy in the world and yet recently admitted that he doesn’t know how to use a computer, the one modern tool shared by everyone from the post-industrial American work force to Middle Eastern terrorists to Pixar animators. Getting shot down over Vietnam may not be a qualification for president in 2008, but surely a rudimentary facility with a laptop is. What Mr. McCain has going for him is a press corps that often ignores or covers up such embarrassments.

The Republican’s digital ignorance is not a function of his age but of his intellectual inflexibility and his isolation from his country’s reality. To prove the point last week, he took a superfluous, if picturesque, tour of Colombia and Mexico, with occasional timeouts for him and his surrogates to respond like crybabies to General Clark’s supposed slur on his patriotism.

For connoisseurs of McCainian cluelessness, the high point was his Wednesday morning appearance on ABC’s “Good Morning America.” The anchor, Robin Roberts, asked the only important question: Why in heaven’s name was Mr. McCain in Latin America when “the U.S. economy is really at the forefront of voters’ minds”?

“I know Americans are hurting very badly right now,” he explained, channeling the first George Bush’s “Message: I care.” As he spoke, those hurting Americans could feast on the gorgeous flora and fauna of the Cartagena, Colombia, tourist vista serving as his backdrop. “It’s really lovely here,” Mr. McCain said. Since he can’t drop us an e-mail, a video postcard will have to do.

Mr. McCain should be required to see “Wall-E” to learn just how far adrift he is from an America whose economic fears cannot be remedied by his flip-flop embrace of the Bush tax cuts (for the wealthy) and his sham gas-tax holiday (for everyone else). Mr. Obama should see it to be reminded of just how bold his vision of change had been before he settled into a front-runner’s complacency. Americans should see it to appreciate just how much things are out of joint on an Independence Day when a cartoon robot evokes America’s patriotic ideals with more conviction than either of the men who would be president.