In a normal year, today would have been the most important day in Laurance Eustis' life.

In a normal year the insurance executive would have been the bewigged and costumed Rex, monarch of Mardi Gras, riding atop a golden float through the city at the head of a parade being acclaimed by more than a million people.

In a normal year, Eustis would have toasted his queen, debutante Deborah Huger, on the balcony of the men's exclusive Boston Club on Canal Street. After the toast, the royal couple would have hurled their champagne glasses to the street to keep lesser lips from touching them.

But this is no normal year. A week ago today, the leaders of 18 paradegiving organizations called off their carnival processions to keep them from being used as pawns in the city's police strike, now in its 12th day.

This action forced the cancellation of all New Orleans parades. Rex did not roll for the first time since Korean War year 1951. It was the first peacetime cancellation since 1875, when the Mardi Gras parade stayed off the street to protest Reconstruction rule.

Instead of reigning over the merrymaking public, Eustis and Huger presided over a day of dancing at the New Orleans Country Club while New Orleanians split up to celebrate the day.

Some went to the French Quarter, despite Mayor Ernest N.Morial's plea for citizens to avoid that traditional focus of Mardi Gras activity, and many others went to the suburbs, where parades were not affected by the police walkout.

"Mardi Gras has survived war, hurricanes, blizzards and yellow fever," said Eustis. "Mardi Gras will go on as before. It's just that we won't parade this year."

Revellers came to the Quarter, but not in the same crush as before. Stationed in the 21 no-auto blocks were between 800 and 900 state troopers, national guardsmen and policemen who have stayed on duty. But except for Bourbon Street, raucous heart of the oldest part of the city, pedestrian traffic moved easily, and all but the most stupefied revellers could find a path along streets that are usually jammed on Mardi Gras.

"We're just here to let them have a good time," said state trooper Robert Fogleman, who lounged against a police barricade with three colleagues, watching the Bourbon Street promenade.

Generally, the French Quarter is reserved for singles, adventurous couples, tourists and people without children. Families usually stake out picnic spots in the broad medians on Canal Street and St. Charles Avenue along Rex's parade route.

But today these medians were deserted. Buses, streetcars and other vehicles rolled by, and leather and jewelry vendor Edward Hayward said, "It's like a regular day. No, it's worse than a regular day, because usually you have people going to and from work."

Even though no parades rolled in New Orleans, today still is a city and state holiday. Attracting a crowd estimated at more than a million was the suburban parade of the Krewe of Argus, which had Loretta Swit -- Maj. Margaret "Hot Lips" Houlihan of CBS-TV's "M*A*S*H" -- as its empress.