The inability of the news media to understand what is really happening in a presidential campaign sometimes approaches legendary proportions. These days, all their attention is focused on the Sept. 11 hearings and the demand that Condoleezza Rice testify to comment on Richard Clarke’s charges. The conventional wisdom says that Bush’s ratings as a wartime commander and leader in the war on terror have been undermined by Clarke’s testimony and book and that the president is in danger of losing his best issue.

But that’s not what is going on.

According to the useful daily tracking polls of Scott Rasmussen, Bush led Kerry by two points before the flap broke out. At the height of the hearings and in the wake of Clarke’s “60 Minutes” TV interview, Kerry moved ahead by 3 points. By the end of the week, the race had again become tied as Bush recaptured virtually all the ground he had temporarily lost.

It is not the ground war that is important right now. It’s the air war between rival campaigns’ paid advertisements. What has happened in March of lasting significance is that John Kerry’s negative rating, according to the Fox News/Opinion Dynamics poll, has risen from 28 percent March 4 to 36 percent March 24.

Bush’s ratings will oscillate up and down, depending on the events of his presidency. But when a challenger’s negatives rise, the increase is forever. Lacking the control over events that an incumbent has, the challenger loses votes permanently as his negatives rise. So far, the negatives are still below 50 percent, but by the end of spring they could be high enough to swamp the Kerry campaign.

For all of his vaunted determination to avoid the mistakes of Mike Dukakis, John Kerry is making the same errors all over again. He is not answering Bush’s attacks.

Bush’s ads hit Kerry for advocating a 50-cent hike in the gas tax. No answer.

The president’s negative commercials criticized Kerry for subordinating the defense of the United States to the decisions of the United Nations. No response from Kerry’s ads.

And when the incumbent told a frightened nation that Kerry wanted to weaken the homeland security protections of the USA Patriot Act, the Massachusetts Democrat was again silent.

The only attack Kerry has answered is the charge that he plans to increase taxes by $900 billion in his first 100 days. His answer is to deny the attack and to reaffirm his backing for a “middle class” tax cut. But voters understand how inelastic the definition of middle class can be and the Kerry answer is not likely to be decisive.

In 1995, I played on the media’s inability to look up to the sky and watch the air war, and on its obsession with events on the ground, by running ads attacking Newt Gingrich and Bob Dole as early as July of that year. We kept the ads off the air in New York and Washington. The press never noticed that we were advertising. Month after month, we saw Dole’s negatives rising, but the media could never tell where it came from even though we were advertising on their own stations!

Indeed, since I believe the current election is really a contest between two issues — terror versus jobs — the Sept. 11 hearings ultimately do not hurt Bush so much as help to underscore the importance of his key issue. The Fox News poll shows that voters agree that Bush would do a better job of fighting terror by 50-27 while crediting Kerry with doing the best at creating and protecting jobs by 48-31.

Neither man is likely to erode the advantage of the other on his foe’s key issue. Bush will still lead on terror, Richard Clarke or no Richard Clarke. Kerry will still lead on jobs, no matter what the economic data show (it takes a long time to filter down from data to reality). So the real question is which issue predominates. Score March as Bush’s month.