NEW YORK. — New York -- ''Politics,'' a young man named Robert Louis Stevenson wrote more than 100 years ago, ''is perhaps the only profession for which no preparation is thought necessary.''
Wrong! A young man named Bill Clinton and an older one named Ross Perot proved that last week. Mr. Clinton, who has never tried much work other than running for office, prepared his whole life for a few days in New York, and he triumphed. Mr. Perot, who spent his life making a great deal of money, thought politics and politicians were jokes, and now he is a national joke.
Mr. Perot thought all he had to do to prove he would be president was to raise the ante, saying he would spend $100 million of his own money to buy the job. And we, the press, bought the bluff.
Thank goodness he quit -- either because he did not really intend to spend the money, or knew that he would still lose even if he did -- sparing us the embarrassment of paying any more attention to his self-generated fairy tale. We fell for the con, suspending disbelief, big time: ''The check is in the mail.'' It wasn't.
At the same time, Mr. Clinton was confidently marching through the mine fields of the Democratic National Convention, capturing or neutralizing other Democratic professionals who thought they could use him to advance their own parades. Jesse Jackson, Jerry Brown, Mario Cuomo, Paul Tsongas and Al Gore, too, were left to salute and carry on as junior officers.
Whatever happens next, the Clinton Convention changed the context of American politics. Some of the changes may be temporary, others are almost certainly permanent, but all are remarkable. These are the themes and stories refined in Madison Square Garden:
1. Generational politics. After eight straight World War II officers in the White House, from the commander in chief to the youngest lieutenant, America may finally turn power over to the Americans born after that war.
2. Forward to the past. Back to aggressive moderation. It may turn out to be an illusion -- Bill Clinton and Al Gore are to the left of the operating American consensus -- but the Democratic Party seems poised to use the men of the '60s to roll back some of the excesses of both the '60s and the '80s.
3. Women, not wives. There is only one thing that the professionals who were in New York understand: votes. Even money, to most politicians, is just a way to pay for more votes. Forget wives and the theorists of feminism; think of two women senators from California. Think of women running for almost every office up for election in 1994 -- because that is going to happen.
4. Jobs, jobs, jobs. This has nothing to do with trade or unemployment statistics. It has everything to do with the Democrats drawn to Washington by the allure of the Kennedys. In middle age or older, they are a kind of self-appointed shadow government. Oh, the broken hearts if Clinton-Gore win and turn to younger no-names in Little Rock and Nashville!
5. Thank you, Jesse. No more Mau-Mauing, please. We owe you. Mr. Jackson, almost alone, vented the anger of black America through the '80s. The danger of government openly hostile to the poor, particularly poor blacks, may be over, or it may be about to erupt in riots or domestic terrorism. But, either way, Mr. Jackson's race is run.
6. Gays become a recognized national special interest, at least for the Democrats. Next the Republicans look for their gay Willie Horton and craft ''family values'' rhetoric to whip up racial division and homophobia.
As Mr. Clinton left New York for points west, it was his election to win or lose. He took the initiative and created the momentum, an amazing achievement for someone running against an incumbent president.
His personal success to date and a mood of change may make him president, but they surely guarantee that this will be one of the meanest and dirtiest campaigns in American history. The Republicans will bear any burden, bare any breast to leave Mr. Clinton as politically dead as Mr. Perot.
That's politics -- and George Bush is a professional, too.
Richard Reeves is a syndicated columnist.