In the end, Margaret Mary O'Shaughnessy Heckler was lucky to be sent to Dublin. The way things are going, she might easily have been sent for coffee.

As a loyal employee, Heckler took pretty good dictation from the president. But the next woman who becomes a secretary in the Reagan Cabinet meetings will probably be taking shorthand.

Showcasing time at the White House is over. The election has come and gone, the gender gap anxiety peaked and waned, and Donald Regan has gone back to the white male talent agency for his central casting.

Betty Heitman, co-chair of the National Republican Party, describes the change in atmosphere more benignly than that. She says, "What has happened with Donald Regan is that he's restructuring the White House so that it's more like a corporate board and everyone reports to him as CEO."

When Donald Regan was last a chief executive officer, of Merrill Lynch, there was one female managing director. Now that Heckler is following Jeane Kirkpatrick, there is only one woman left on the "board" of this corporation: Elizabeth Dole. Regan must feel right at home.

Not a single woman attends senior staff meetings at the White House. Not one regularly sits at national security meetings any more. Nor, since Faith Whittlesey's departure from the job of public liaison to be ambassador to Switzerland, is there any woman who reports directly to the president. Only Nancy Reagan has risen in mythical power as other women have fallen in real power. Every time someone like Heckler is removed, Nancy is trotted out as an invisible remover.

In effect, Peggy Heckler was cast out (get thee to an embassy) because she was no longer needed. She and Elizabeth Dole were appointed within months of each other in 1983, when it looked as if the Republicans had better have a few highly visible women for campaign show and tell. She was, as she liked to say, the administration's "voice of compassion." Her soprano was brought on political stage all through the campaign as a counterpoint to the Democratic theme song about "fairness."

In the last five years or so, Heckler had a tough time finding a place for herself as a moderate Republican woman. Pro-ERA and pro-Reagan, she was often caught in the middle. She lost reelection to Congress in 1982 to liberal Democrat Barney Frank. Even feminist organizations endorsed Frank because of Heckler's record opposing abortion. But as head of Health and Human Services, she both toed the Reagan line and sometimes held the line. Conservatives complained that she wasn't ideologically pure enough.

When push came to shove, there was less support for Peggy Heckler than there had been for Labor Secretary Ray Donovan. The administration has stopped worrying about t women's vote; Heckler had little political base left in the party and no old-girl network in the administration. She was a goner.

For many of the same reasons, the women's place in this house is much shakier. In general the administration's record on appointing women is better today than in the first years. In 1984, 17.4 percent of what Congressional Quarterly calls major appointments went to women. In 1985 the figure is holding at 15.5 percent. But when you look at the concentric circles of real power, the inner rings are nearly void.

Faith Whittlesey, once ranking woman in the White House and an anti- ERA conservative, realized this as she drove away from her old job on Pennsylvania Avenue. She told The Wall Street Journal, "All I saw was a sea of men coming and going in those cars. I began to think, maybe they're right. Women aren't welcome in the White House."

Even Jeane Kirkpatrick, a soldier of conservative fortune, talks about the campaign to keep her ambitions in check: "One male colleague . . . said that I was too temperamental to hold a higher office. What do they mean -- too temperamental once a month?"

The public attack on Heckler was not of temperament but of incompetence. As she said in a perhaps prophetic interview, "There's far more tolerance of incompetent males." It's fair to observe that Heckler was judged by that old double standard: any woman less than twice as good wasn't good enough.

The White House likes to say that they've gone beyond tokenism and window-dressing. But today, without election-year pressure or a safety network of women on the inside, even the windows are looking awfully empty.