Following the last debate many pundits reckoned on a McCain rebound–but his numbers actually slipped. And according to conventional wisdom, endorsements rarely have much influence on the course of a presidential campaign–most voters want to make their own call. But searching for an explanation, it’s hard to avoid the influence of a single endorsement: that of former Secretary of State and chairman of the Joint Chiefs of Staff Colin Powell. In future elections, I believe the Powell endorsement will be studied for its content, timing, and the critique it carried—it was one of the most effective endorsements of all time. Similarly, the efforts undertaken to blunt it were so extraordinarily clumsy that they actually helped make the endorser’s point when he criticized the McCain campaign. So why was the Powell endorsement so consequential?

First: the content. Powell made an effective case for Obama as a leader in times of trouble, providing reassurance in regards to the area where the candidate has, until recently, faced the most doubt: foreign policy. He also offered a side-by-side comparison with McCain with respect to the management of economic issues.

Second: the timing. Powell’s career has been marked by an ability to discern the moment when a step can be taken with the most effect. By delivering his endorsement at the commencement of the last phase of the campaign, after the last debate, but before presentation of the candidates’ closing arguments, Powell picked the critical moment.

And finally: Powell made clear that he was opposing a friend of 25 years at some personal cost but for principled reasons. He believed that McCain would make a fine President but he was concerned by McCain’s uneven response to crisis, by his selection of Sarah Palin, and by the tone and tenor of his campaign–framed on an appeal to the baser instincts of the population. Indeed, if one passage of the Powell endorsement is preserved by posterity, it will be the remarkable image he presented of the young mother of a Muslim soldier killed in service to country:

Is there something wrong with being a Muslim in this country? The answer is no. That’s not America. Is there something wrong with a seven-year-old Muslim American kid believing he or she could be president? Yet I have heard senior members of my own party drop the suggestion that [Obama] is a Muslim and might have an association with terrorists. This is not the way we should be doing it in America.

I have spent the last week in two Muslim nations which have recently been close allies of the United States and in the course of my travels I kept thinking back to these lines. Both nations I visited host American military installations and are proud of their ties to the United States. In both countries I found that the American presidential election was being followed with extraordinary attention. And in both I found a tremendous level of upset about the rhetoric coming out of the McCain campaign. “Okay, perhaps McCain is not an anti-Muslim bigot,” one college student told me, “but he seems to think that the best way to be elected president is to whip his fellow citizens into an anti-Muslim frenzy. Our nation is America’s ally, but I can’t avoid thinking, watching the McCain campaign—is this man going to make war on us too?” The young student was voicing in his own way a concern like Powell’s. Why can’t McCain the candidate articulate America’s dreams? Why does he have to concentrate fear, ignorance and hatred?

Here is the Powell endorsement, delivered on NBC’s Meet the Press:

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Of course there are also endorsements that hurt. As President Bush went to the polls to cast an early ballot for his choice, John McCain, Saturday Night Live offered a comic endorsement in that vein, and Will Ferrell returned to SNL for the event.

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