Benjamin C. Bradlee, the executive editor of The Washington Post, is a proud man. He doesn't like his paper beaten on a news story. Last week it happened. The Wall Street Journal had a front-page story recounting the "legal and personal problems" of John M. Fedders, who resigned last week as enforcement director of the Securities and Exchange Commission.

What follows is the anatomy of the Post defeat -- a tangle of missed opportunities, tightly compartmentalized departments, news executives who were left uninformed and even the side effects of carpentry hammering and sawing -- all of which contributed to the Wall Street Journal triumph.

Sometime last year a business section reporter, Michael Isikoff, who had covered a securities case involving Mr. Fedders, got a tip about the SEC official's misconduct at home and asked Tom Vesey of The Post's Montgomery County bureau to check court records. As Mr. Vesey recalls it now, he checked and found a divorce case had been filed and there "might have been some mention of physical abuse." Mr. Isikoff said he called Mrs. Fedders, but she was not willing to discuss the matter. He called her again in November, but again she declined. Mr. Isikoff said he reported his contacts to Jerry Knight, deputy business editor of The Post, and there it ended.

The next alert came to the national news section. Last fall a free-lancer, Richard Volkin, writer and lawyer, described the wife-beating episodes to Judy Nicol, assistant national editor, and added the information that the wife complained about the violence in a letter to President Reagan, which he believed had been "handed to Fred Fielding," the White House counsel. But her boss, Peter Milius, decided that since the court or hospital records of the Montgomery resident would be found in the county, "it's a Metro story."

The Metro section, which is responsible for Maryland, Virginia and District of Columbia coverage, was interested -- if skeptical -- in the free-lancer's report. After consulting with assistant managing editor for Metro Larry Kramer, Maryland Editor Laura Stepp assigned Montgomery County Bureau Chief Robert Melton to look into the political aspects and Montgomery reporter Victoria Churchville, who covers the county courts, to check court papers and interview the wife and persons with congressional oversight on the SEC.

Miss Churchville, who had been a reporter for States News Service and the Orlando Sentinel, found court papers filed in 1983 by Mr. Fedders' wife, Charlotte, seeking an uncontested voluntary separation, later changed to a contested separation, with reference to "arguments in the family," according to Miss Churchville. She called Capitol Hill sources and found one staffer who had heard rumors of wife-beating. She sought time for an interview with the wife, but did not pursue it aggressively, nor did her editor. Her bureau chief, Mr. Melton, considered her the principal reporter on the story and awaited her report.

While the story raised questions of privacy and privilege to report facts, this became moot when, on Feb. 4 and 5, the public trial began in Montgomery County Circuit Court. During this period, the bureau office in Rockville was expanding, and carpenters were busy moving walls and installing shelving, and so Miss Churchville covered her beat by telephone from The Post's downtown Washington office. She missed the trial, as did other area newspapers.

On Feb. 25, The Wall Street Journal laid down a 4 1/2-column-long story by Brooks Jackson. Mr. Bradlee came to work "smoking" -- and I don't mean tobacco. He convened a meeting of top editors and learned that while he and Managing Editor Leonard Downie Jr., were in the dark, three departments had prior knowledge of the story; two had the same news alert as the Journal; and, despite the fact that the story was in The Post's territory, "we blew it," in the words of Metro editor Kramer. No effort had been made by national or metro desks to involve The Post's White House reporters to seek information about the letter from Mrs. Fedders to President Reagan.

Mr. Bradlee attributes the setback to the lack of local competition. He recalls the days when he covered courts for The Post, and there was all-out rivalry with reporters from the Times-Herald, Evening Star and Daily News. In retrospect, several editors have acknowledged that coverage should have been more directed and, as one put it, "we should have had everyone work on it."