With all the grace and good will that one associates with fratricide in Lebanon, the Democratic Party has elected a new chairman. The party might now do well to seriously consider its condition.

It is a party haunted by three facts and a phrase. The phrase is the most important.

The first of those facts is that the Democrats are the more liberal party in a country becoming somewhat more conservative.

The second fact is that the conservative tide is backed up by a major geographical movement. The much discussed "move to the Sunbelt" is also a move to more conservative areas. A Democratic presidential candidate can carry every Frostbelt state in 1984 and still lose the election by an electoral count of 288-250.

The third fact is that the new election rules provide that in 1984, will get almost $4 million in public money to run a presidential campaign that will almost surely siphon liberal votes away from the Democratic nominee.

And now the phrase: "me too."

To understand what has happened, one must first understand that Ronald Reagan has pulled off the biggest political heist in American history. He swiped the whole party, the old Democratic one. Consider just a few aspects of that party. It was the old Democratic Party that first understood that totalitarianism (of right or left) was the menace of our time. It said that a strong, assertive America would have to play the role of world superpower. The Republicans at the time were isolationists.

The old Democratic Party was the party of "growth economics," of tax cuts, of what was then called "belching smokestacks." The pristine environmentalists of that earlier time were Republicans, usually called conservationists as well as conservatives.

The old Democratic Party was the party of "merit." The cards in the subway cars of the very Democratic city of New York showed a picture of white boys on a baseball field, with a black youngster on the sidelines. The leader of the white boys was waving the black youngster onto the field, remonstrating to his teammates: "What's his color got to do with it? He can pitch!"

The Republicans of that time were sitting on the boards of admissions of Ivy League universities, quietly enforcing quotas to keep Jews and blacks out of gentlemen's schools.

And now Ronald Reagan and his Republican cohorts have swiped most of those basic traditions. Reagan's the tough guy on the block (attacking Democrats for being isolationists). He's Mr. Growth Economics (attacking Democrats as environmental regulatory no-growthniks). He's for merit (attacking Democrats for being for quotas).

To add insult to theft, he's the fellow who says he'll protect "the safety nets" (Social Security, Medicare, etc.) that his party regularly opposed. To all that he has added some legitimate old Republican free-enterprise smaller-government ideas and -- presto! -- it's a "New Beginning."

How will the Democrats cope with this? There was no hint at the first post-election gathering of the Democratic National Committee. The big issue was how to quota in women, blacks, Hispanics, Asians, etc. During the argument, someone must have risen to say: "Who cares if he can pitch? He's female!"

Democratic leaders piously said that what the party needs is unity, money and organization. They left unresolved only one simple question: unity, money and organization for what?

What does the Democratic Party stand for? One wing, unwilling to give away the game, says strength, growth and merit. Those ideas, they say, are our ideas; we can shape them better than the Republicans.

The other wing says, hey, those are Reagan's ideas. We can't be the "me too" party. They now say the Democrats need "new ideas." But they won't tell us yet what they are.

Democrats must face the music. They are not in trouble because they have no money, organization or unity. Exactly the opposite: They have no money, organization or unity because they are in trouble.

They are in trouble not because they stand for nothing but because they stand for two very different things. Some believe in the old Democratic beliefs (temporarily pilfered by Reagan). And some still believe in the new Democratic beliefs that got them into all the trouble they are in.

The Democrats' choice is unfortunately simple. They can go left, splitting up an ever-smaller liberal pie with John Anderson's federally funded party. Or they can go back to their roots, try to split off the Reagan voters who were stolen from them and do battle against the tough facts of ideology and geography.

Sooner or later in this game, ideas and philosophy are carried by Democratic national candidates, not Democratic national committees.

The potential nominees in 1984 will all be tempted to split the difference within the party. That is a tropism in American politics. They will be tempted to be for strength-but, growth-but and merit-but -- just the policies that characterized the Carter administration.

If that happens, Democrats will have a party-but -- a party, but without an idea, a posture, a direction or a stance, just those things a party needs to get elected.

Many Democrats now feel that if the party is to regain a fighting stance, there will first have to be a fight. Me too.