WASHINGTON — For Tricia Nixon's 1971 wedding, the Vietnam War protesters camped outside the White House agreed to take their bullhorns down the street, but only until the ceremony was over.

In 1906, Alice Roosevelt's ceremony in the East Room after a Grand Hallway entrance was literally swoon-worthy — several guests reportedly passed out from excitement.

When Maria Monroe (the first White House daughter to marry during her father's presidential term) decided to exclude foreign dignitaries from her 1820 guest list, it caused such a backlash that some speculate it informed the creation of the Monroe Doctrine.

Jenna Bush has a hard act to follow.

A White House wedding is the perfect nexus of celebrity-spotting, couture gowns and young love — with just enough wonk thrown in to explain even dour politicos' obsession with the nuptials. The Washington Post covered Alice Roosevelt's Feb. 17 wedding by eschewing all other front-page news stories in favor of a blown-up picture of the bride, calling her the "daughter of all American people" and her wedding "a blessed union of the hearts and hands such as is possible nowhere more than in the United States."

Los Angeles may have the Oscars and New York the Tony Awards, but Jenna Bush in Zac Posen, floating through the East Wing on the arm of her teary-eyed president-dad? Washington could own that show.

Or, at least it could if Jenna decides to marry Henry Hager in the White House — which would be the 10th such wedding in executive mansion history. (Some presidents' children have elected to exchange vows at alternative locations: Newly converted Catholic Luci Baines Johnson, for example, was married at the Shrine of the Immaculate Conception.) Tony Rodham, Hillary Clinton's brother, married Nicole Boxer in the Rose Garden in 1994. But the last child of a president to wed at the White House was Tricia Nixon 36 years ago.

When Lucy Winchester Breathhit, Pat Nixon's former social secretary, is asked to remember the planning of that event, Breathhit — who now lives in Kentucky — begins by offering a message to the entire Washington, D.C., area: "Congratulations! Congratulations on getting a wedding!"

SURPRISES HAPPEN

Aside from our fascination with the personal lives of presidential kids — Chelsea Clinton's endearingly awkward years, the Bush twins' blossoming from party gals to do-gooders — weddings have been known to offer new insights on presidents: When the minister at Lynda Bird Johnson's marriage to Charles Robb asked, "Who giveth this woman to be married to this man," President Johnson responded not with the traditional "I do," but with the more feminist "Her mother and I." Lynda Robb told People magazine in 1994, "I had never realized he was that progressive."

"If Jenna got married in the White House, it would be a tremendous boost to (President Bush's) popularity," says Doug Wead, former special assistant to the first President Bush and author of "All the Presidents' Children." "Nixon received a lot of good will because of Tricia's wedding. I've said before that President Bush's best chance to come out of his term well is if they capture Osama bin Laden and one of the twins gets married."

Of course, there are less-cynical reasons a couple might choose a White House wedding. The place already has a no-fly zone, protecting the betrothed from the chopperazzi attacks that plague other celebrity couples. And the Secret Service probably has a code-named protocol for handling drunken uncles who try to start up the "Chicken Dance."

HIGH ANXIETY

Still, those who have been charged with planning the marriage of a president's child know how quickly the blessed event can become a quagmire wrapped in fluffy pink tulle.

Just ask Bess Abell, Lady Bird Johnson's social secretary, who organized both Lynda's White House wedding and Luci's 1966 White House reception. While Lynda would later leave her gown concerns to designer Geoffrey Beene, Abell says, Luci wanted the traditional experience of visiting bridal shops with her bridesmaids. After several secret excursions — one ruse involved Abell pretending to dress-shop for her sister — Luci settled on a design by Priscilla Kidder. One problem: Priscilla of Boston was a nonunion shop.

David Dubinsky, then president of the International Ladies' Garment Workers Union, angrily phoned President Johnson, Abell says. A compromise was reached: Pieces of the dress were outsourced to acceptable factories so that the majority of the gown was union-made. (Perhaps in a nod to the experience, "The West Wing" aired an episode dedicated to the politics of President Bartlet's daughter Ellie's wedding dress.)

A few similar fiascos, Abell says, eventually led to her receiving a late-night phone call from President Johnson. "He said, 'If there's one mistake that could be made on this wedding and you haven't made it, it's because you haven't thought of it.' "

She laughs at the memory now, but in 1968 Abell told Time magazine that working on Luci's and Lynda's weddings had "given her no regrets" about her own decision to elope.

Things were smoother, but no less public, for Lynda's wedding the next year. Reporter Bonnie Angelo, a 30-year veteran of Time, was assigned to stand behind makeshift drapery and record Lynda's every move. "They cut a little hole so I could see every magical moment," says Angelo, who spent the entire ceremony kneeling on the floor behind the partition. "And for that I bought a new velvet dress."

WINDOW OF OPPORTUNITY

Tricia Nixon's wedding later had its own small foibles. Shortly before her marriage to Edward Cox, the White House released a scaled-down version of the couple's cake recipe. The New York Times took it upon itself to test it and on June 2, 1971, declared it inedible: "mush on the outside and soup on the inside." (The White House pastry chef later cleared up confusion by instructing eager cake bakers to add a paper collar around the top of the pan.)

On Tricia's wedding day, rain clouds threatened to ruin her wishes for a Rose Garden ceremony. Breathhit remembers holing up in a crisis room with her staff, getting weather updates by phone from an Air Force meteorologist — one resource not available to the typical bride. "Finally she said, 'In 23 minutes you will have a 14-minute break in the weather,' " Breathhit says. "When the go was given, we grabbed the chairs and raced outside, plunking them in the garden."

The drizzle held, for the most part, and Tricia Nixon recalls her father insisting that a little water wouldn't ruin anything. "He said, 'Gentle rain caresses a marriage,' "she remembers.