Barack Obama has long said that his campaign will not accept contributions from lobbyists, and now that he is the presumptive nominee, the Democratic National Committee won't accept them, either.

John McCain says that his campaign won't employ lobbyists, and volunteers are now queried about possible lobbying activity in the past. It's only a matter of time until someone calls for a law requiring every lobbyist to paint a big, red "L" on his forehead.

Behind this stigmatization of lobbyists is the notion that the failure to produce legislation in the public interest stems from the existence of lobbyists. Which is obviously nonsense. We couldn't abolish lobbying without repealing the First Amendment, which gives all of us, even those who are paid to do it, the right to "petition the government for a redress of grievances." And the government could not sensibly do business without lobbyists -- as Hillary Clinton recognized at the YearlyKos convention last August.

While Obama and John Edwards were lambasting lobbyists, Clinton said: "You know, a lot of those lobbyists, whether you like it or not, represent real Americans. They actually do. They represent nurses. They represent, you know, social workers. They represent ... yes, they represent corporations. They employ a lot of people."

Lobbying is as American as apple pie, going back to colonial times. The Rev. Increase Mather lobbied in London for a new charter for Massachusetts. Benjamin Franklin was the colonial agent -- lobbyist -- for Pennsylvania and other colonies. When the federal government was created, lobbyists for varied interests naturally swarmed to the capital -- first New York, then Philadelphia and Washington.

It is a simple fact of life that when Congress writes laws and the executive branch writes regulations that channel vast flows of money -- and laws and regulations that have vast moral implications -- citizens affected by those words are going to try to make sure they're written the way they want. They're going to hire the best people they can find to do so. They want lobbyists with connections -- and with expertise. They can help lawmakers understand how the words they write will affect "real Americans."

That's why I was pleased to see Clinton defend lobbying not only for those whom her Democratic audience considers good interests (nurses, social workers) but those they don't (corporations). Implicitly, she's rejecting the distinction made by the head of the Humane Society of the United States, who recently contrasted "special interest lobbyists" (presumably those working for profit-making interests) with "socially responsible lobbyists" (those working for nonprofits). But even lobbyists for nonprofits have a monetary motive: to keep their (often six-figure) salaries flowing in.

Yes, K Street is not perfect. Old entrenched interests tend to be well represented. New and growing industries and morally motivated constituencies that are unorganized tend to be underrepresented. The high-tech industry figured it could get along without much representation in Washington until Microsoft got slapped with an antitrust suit a decade ago. Now, it hires lobbyists in droves.

Not much of this will change in a McCain or Obama administration. The campaigns currently are embarrassing themselves by stigmatizing lobbyists. Obama's initial choice to head his vice presidential selection committee was Jim Johnson, who as CEO of Fannie Mae in the 1990s ran one of the most effective lobbying operations in town. McCain has had at his side through the campaign Charlie Black, who was a very successful lobbyist for more than 20 years.

More important, both candidates are proposing healthcare, carbon emission and tax changes -- legislation that will, and should, face heavy lobbying. Which is fine: Such laws will have enormous ramifications, and everyone who wants to should chime in. Even -- if I can use that dreaded word again -- lobbyists.