How an affair between a reporter and a security aide has rattled Washington media

The revelation of Ms. Watkins’s affair with Mr. Wolfe stunned many journalists who had watched her ascent from college-age intern to rising star in the sensitive field of national security reporting. Their relationship played out in the insular world of Washington, where young, ambitious journalists compete for scoops while navigating relationships with powerful, often older, sources.

Avoiding conflicts of interest is a basic tenet of journalism, and intimate involvement with a source is considered verboten. In her short career, Ms. Watkins disclosed her relationship with Mr. Wolfe to her employers in varying degrees of detail — sometimes citing Mr. Wolfe’s name and position, and sometimes not — while asserting that she had not used him as a source during their relationship.

If the romance with Mr. Wolfe raised any red flags, they were not enough to prevent several news organizations from hiring Ms. Watkins, or to persuade her editors to move her off the intelligence beat. Since meeting Mr. Wolfe in 2013, Ms. Watkins reported on the Senate Intelligence Committee for Politico, BuzzFeed News, The Huffington Post and McClatchy, where her reporting was part of a submission that was a Pulitzer Prize finalist.