Yesterday, Senator Edwards gave an address at Riverside Church in New York City’s Morningside Heights neighborhood. He exhorted Americans to make clear their disapproval of the Bush administration’s plans to send more troops to Iraq, with letters, phone calls, and protests.

Mr. Edwards chose just the right venue — 40 years ago in the same church, Martin Luther King gave a speech against the Vietnam War.

That speech became a touchstone of King’s career, and I know that in watching Mr. Edwards’ tribute to King, I was supposed to see a good man doing the right thing.

But I also saw hopeless impotence. That is because any plan or speech Mr. Edwards or like-minded people come up with is largely just spitting into the wind as long as we don’t have a draft.

You’d think that King would have been the one who was tilting at windmills. In 1967, the pacifist strain was not as strong in mainstream thought as it is now. In his speech, King recounted being asked by intelligent people, “Why are you speaking about the war, Dr. King? Why are you joining the voices of dissent?” Here was an era when even New Yorker-reading bien-pensant people could tell King things like “peace and civil rights don’t mix.”

Not to mention that King was a black man in an America just past legalized segregation and at a phase in his career when his star had tarnished among both blacks and whites.

Although King took an awful lot of criticism for his speech, he played a part in a growing peace movement that ended up having much to do with the pullback from Vietnam. In the newsreels, it can look like half of America lived in the streets protesting for a good three or four years.

Mr. Edwards, in his speech, seemed to think that the only difference between then and now was that, for some reason, an epidemic of apathy has hit America. So our job is, as he put it, “to reject the easy way of apathy and choose instead the hard choice of action.”

More specifically, he said, “Tell your elected leaders to block this misguided plan.” But the same day that he made the speech, the president and vice president were on television insisting that the opinions of anti-war legislators would have no effect on their escalation of the war.

Many old lefties presume that the pitch of protest that we remember from the Vietnam days could cut through even Messrs. Bush and Cheney’s resolve. In other words, America would need to produce some serious protesting — surging masses of furious people out in the streets day after day, boycotts, and work stoppages. That is, the kind of protesting that would present such clear opposition from so many Americans that the White House’s serene disregard of public opinion would start to seem anti-democratic.

There would have to be, as it were, a Walter Cronkite moment, when claims that we are making progress in Iraq were officially deemed too peculiar and anti-empirical to be accepted as mainstream opinion.

But the rest of us know that no matter how loudly the bloggers clatter and no matter how angry the bumper stickers get, we will never see protests like that about Iraq. And much of the reason is that so few of us are faced with sending a loved one into the fray — much less going into it ourselves. If all of us had had to go to war, then there would have been a more urgent sense to pull out of it sooner when the war plans started falling so grievously to pieces.

Rep. Charles Rangel suggested the reinstatement of the draft a few months ago, and his statement was largely treated as a colorful salvo worthy of a few days of press commentary, much of it dismissive. This was wrong, and Mr. Rangel is right.

It can sometimes look as if the fever-pitch protests against Vietnam were because of something wonderful about the era itself. But surely, the looming reality of death in the Vietnamese jungle had a way of pulling you, your girlfriend, and your parents out into the streets.

For the record, I was in favor of the Iraq war when it began. When a cousin of mine was stationed in Kuwait in preparation for relocation to Iraq, I thought of him as on his way to a worthy mission. I am, quite avowedly, one of those people who have come to oppose the war based on how it has been conducted.

And in that light, cousin Jerry is back now, and today I would be revolted to see him dragooned off to Iraq to help “stay the course,” when the course so clearly leads to nowhere.

In the clinical justifications we often read and hear for continuing this war, what usually is missing is any sense of whether our “interests” in Iraq are still worth our sending young Americans to be blown to bits.

We need a draft to force our leaders to face up to that. The draft helped people like King get across a peace message that today few of us question the wisdom of. Now, only a draft could put teeth in a similar peace message that will be considered similarly wise 40 years from now.

Mr. McWhorter is a senior fellow at the Manhattan Institute.