We got an e-mail today from one of Hillary Clinton's campaign spokesmen. It said that we "might want to check out Hillary Hub this morning," and it provided a link to make it easy for us to do so.

What we found there: a banner that says "The Politics of Hope," video clips of Barack Obama and John Edwards talking about "the politics of hope," and four newspaper and wire service headlines about how Obama and Edwards are going after Clinton.

The implication? Attacking the views of another Democratic candidate means either that you've turned your back on the "politics of hope" or that you never really believed in the idea in the first place.

But don't just take our word for it. As we began to write this post, we received another e-mail message from the Clinton campaign. This one, a memo to "interested parties" from Clinton strategist Mark Penn, accuses Edwards and Obama of having "abandoned" the "politics of hope" by declaring that they're "going to go negative" on the Democratic front-runner.

Here's our memo in response: Stop.

When Obama spoke of the "politics of hope" during his speech at the Democratic National Convention, he did so to contrast it with what he called the "politics of cynicism" and the "politics of anything goes," the "spin masters" and "negative ad peddlers" who would divide Americans, liberal against conservative, black against white, red state against blue.

If Obama was suggesting that one candidate couldn't or shouldn't make it clear that he disagrees with another on matters of substance, well, he didn't say that then, and he's not saying that now.

In an interview with the New York Times last week, Obama said he's "amused" by "some of the commentary out of the Clinton camp, where every time we point out a difference between me and her, they say, 'What happened to the politics of hope?'" It's a "silly" question, he said. Why? Because, he said, "the notion that somehow changing [the] tone means simply that we let them say whatever they want to say or that there are no disagreements and that we're all holding hands and singing 'Kumbaya' is obviously not what I had in mind and not how I function."

Nor is it the way the Clinton campaign functions. While Clinton herself generally -- but not always -- stays above the fray, the Clinton campaign routinely reaches out to reporters to provide information they might use to attack her Democratic opponents. Some of it comes in public statements like the Penn memo the campaign sent around today or the harsh, on-the-record comments Clinton spokesman Phil Singer has made about Edwards' "flagging campaign" or Obama's "same old attack politics."

Much more of it comes in behind-the-scenes e-mails to newspaper reporters and bloggers -- the sorts of e-mails we get from the Clinton campaign but not from the Edwards or Obama camps: On the "off-chance" you didn't read it, here's a copy of a Washington Post editorial calling Obama "irresponsible"; just "wanted to flag this item" in which the Huffington Post criticizes Obama on Iran; here's something Edwards just said about Iraq, and here's something contradictory he said earlier.

The last of those came in an off-the-record e-mail message we received from the Clinton campaign late last month. We're probably breaking the rules in mentioning it, but we figure it's fair game: If you're going to claim that the other guys are doing something wrong in calling your candidate's views into question, you don't get to pretend that you're not doing the same.

But our larger point here isn't that the Clinton campaign's "politics of hope" argument is hypocritical -- although when Penn says that Clinton is "defining the 'politics of hope' while the others are abandoning them," it is. The larger point is that the Clinton campaign's argument is off the mark, offensive and, ultimately, unhelpful.

If Clinton's Democratic challengers were attacking her with the phony scandals of the 1990s -- the "politics of personal destruction" -- or smearing her with the "undermining the troops" and "advocating America's defeat" crap that's the stock in trade of the GOP these days, then her campaign would be right to be asking about the "politics of hope." But the last time we checked, Obama was criticizing Clinton for her positions -- or lack thereof -- on issues such as Social Security, Iran and Iraq. Moreover, he has been doing it with remarkably noninflammatory language. Neither his talk of "triangulation and poll-driven politics" nor his accusation that Clinton will "dodge and spin" to avoid answering questions is what we'd call incendiary. Yes, Edwards' attacks on Clinton have been sharper, but they're still miles away from the Swift-boating, gay-baiting, race-card-playing hardball that any Democratic nominee can safely expect to see in 2008.

More to the point, isn't this exactly the sort of debate that candidates and their party ought to be having along the road to the White House? Since 9/11, Democrats and their political allies have spent six long years on the receiving end of lectures about why they can't say what needs to be said. Bill Maher's criticisms of the president draw a watch-what-you-say warning from the White House; Tom Daschle's concern about the president's rush to war in Iraq leads the Republican speaker of the House to accuse him of coming "mighty close" to providing "comfort to our adversaries"; the president's chief political advisor says Dick Durbin's comments about Guantánamo have put our troops "in even greater danger" than they were before -- even after Durbin apologizes for saying what he said. Then Congressional Republicans -- with some help from too many Democrats -- turn a chance to debate America's role in Iraq into an opportunity to condemn MoveOn.

The last thing the Democratic Party needs now is somebody else -- let alone one of its own -- suggesting that open debate is somehow wrong. Clinton seemed to understand that point perfectly well when she announced her candidacy back in January. "Let's talk, let's chat," she said then. "Let's start a dialogue about your ideas and mine, because the conversation in Washington has been just a little one-sided lately, don't you think?"

Yes, as a matter of fact, we do. But a one-sided conversation is a one-sided conversation, no matter who's doing the talking. Elections are necessarily choices among competing candidates and competing visions. If Clinton can run her campaign without ever mentioning why she thinks she's better than her opponents, more power to her. But mere mortals can't do that, and they shouldn't have to. If Clinton was serious about having a "dialogue" -- if part of her own hope for America is that we'll have a more open society than the one in which we've lived for the past six years -- then it's high time for her campaign to stop trying to shame its opponents into silence. Engage with the criticisms or ignore them; just don't argue that it's wrong to raise them in the first place.