It's a tense time.

We're entering the last four weeks of the presidential campaign in the midst of enormous financial uncertainty. What we need is calmness, thoughtfulness. I thought both candidates at last night's debate were calm and relatively thoughtful, though McCain's war injuries tend to make him look stiff and combative. On the whole, though, McCain and Obama managed to answer most of the questions, got solid information across, and appeared qualified for the job (as Sarah Palin resoundingly does not).

Away from the debates, though, the campaign gets uglier and uglier. And more and more irresponsible.

Both McCain and Obama are twisting and exaggerating - McCain, in my opinion, more often, and more egregiously. But the point is, neither needs to do this. There are plenty of issues to discuss. If they believe in putting Country First, as McCain likes to say, it's time to start doing it. Our problems are too complex, and too serious, to indulge in this mudslinging. The campaigns are demeaning to them and harmful to the country.

And the mudslinging, the innuendos, the exaggerations, the fabrications - the appeal to base emotions - come with a cost.

We saw one of those costs at Sarah Palin's rally in Clearwater, Florida, yesterday. Palin, thoroughly enjoying herself, fired up the crowd by saying she had been reading the New York Times recently. "Boooo," shouted the crowd. Then: One of Obama's early supporters was "a man named Bill Ayres," the subject of a Times article last weekend. Another "boo" from the crowd. Then: A reference to Ayres' membership in the Weather Underground. Another boo.

And then: A shout of "Kill him!" from a man in the crowd.

Was he referring to Ayres? To Obama?

It hardly matters. This is the dangerous territory we've entered.

The "Kill him!" shout was audible on a broadcast of the rally, but Palin, who was on a roll, may not have heard it, or it might not have registered.

The remark has now been publicized, though. So have racial slurs hurled at a black camerman at a recent McCain rally. It's time for Palin and McCain to disown this stuff, express their horror and regret, and be on the alert for reactions like that in the future.