WASHINGTON – To everyone’s surprise, Dr. Howard Dean’s first treatment for the ailing Democratic Party was a dose of tranquilizers.

The former Vermont governor and firebrand contender for the 2004 presidential nomination was so calm and soothing in his first appearance as the newly elected chairman of the Democratic National Committee last week that he almost lulled his audience of rabid partisans to sleep.

While launching a few darts in the direction of the Bush administration, Dean was careful not to jar the sensibilities or raise the hackles of any Democratic faction. The man who had campaigned in 2003 as the voice of grass-roots activists frustrated by what he called the timidity of their Beltway-bound leadership settled into his new role as head of the party establishment as if he’d been groomed for the job.

The reality, as he knew better than anyone in the Hilton ballroom, is that he was about the last person most of the big players – the unions, the donors and especially the elected officials – wanted in command. But the power brokers never could agree on a candidate of their own, so Dean won without owing any of them much of anything.

He realized that his first task was to reassure those who were nervous about the sometimes strident antiwar and populist rhetoric of his presidential campaign that he would not make it easy for Republicans’ to pigeonhole him as a loudmouth elitist Northeastern liberal.

So he clung tightly to the most mainstream of positions, describing the Democratic Party as one that is “fiscally responsible (and) socially progressive.”

That was actually his record during his years as governor of Vermont, but when he became a national candidate, he moved to the left and seized on the burgeoning opposition among Democratic activists to the war in Iraq.

In his debut speech as party chairman, however, he skipped over foreign policy and when asked specifically about Iraq in a post-speech news conference, he ducked the subject. He told questioners that his views have not changed, but declined to repeat them, adding that, “Most of the policy pronouncements are going to be coming from the leadership of Congress, not from me.”

This deference to Washington officialdom is a dramatic change for candidate Dean, who never bothered to conceal his disdain for those such as John Kerry and Dick Gephardt who built their careers on Capitol Hill.

But it is consistent with what he told the members of the Democratic National Committee when he was seeking their support for the chairmanship. You could get a clear sense of what they found appealing about Dean if you listened to the nominating and seconding speeches that preceded his election by acclamation.

Wellington Webb, the former mayor of Denver and (briefly) a rival for the chairmanship, called Dean “a fighter” and the first in the 2004 field to “take on George Bush, energize the grass roots and show us how to raise money on the Internet.”

Others said they thought that as a former governor, he would help strengthen state parties, or that his Vermont background would give him a feel for rural politics, or that he could attract young people to the party.

Clearly, Dean had managed to be different things to different people in the campaign for the chairmanship – a political skill he will need if he is to survive in the job.

He faces nothing but daunting challenges, starting with the task of balancing his own life. His physician wife is remaining in Vermont; he will live part-time there and part-time in Washington, and inevitably will spend a good deal of time on the road, raising money and trying to pump up organization efforts for the off-year elections.

His stated inclination to leave the policy pronouncements to elected officials will not be easy for a man of his pronounced views to maintain over a four-year stretch. And there is a potential cost for Democrats if Dean truly tries to foreclose giving the party its own policy voice.

Congressional leaders necessarily trim their views to meet immediate tactical needs. That’s why, for example, Capitol Hill Democrats are withholding any Social Security rescue plan of their own until President Bush spells out his own proposal.

But the party needs a longer-term and broader perspective, one that includes and reflects the experience of state and local officials as well as Washington voices. The party chairman is the right person to organize such a policy council, and if Dean doesn’t do it, it probably will not get done.

Diffidence may be momentarily reassuring, but it is not a long-term posture for success.

David Broder is a Washington Post columnist. Contact him by writing to davidbroder@washpost.com.