WASHINGTON  — The message from Hillary Rodham Clinton: Trust me. But in a 21-minute news conference to address why she used a private email account as secretary of state, the favorite for the Democratic Party’s presidential nomination in 2016 did little to try to build that trust among those willing to give her the benefit of the doubt.

Granted, that may be a thin slice of America. Few people inspire more clear-cut devotion and antipathy than the former first lady, senator and diplomat. Still, as she nears the launch of her presidential campaign, Clinton might have used the occasion of a rare news conference to reach out, to make a special effort to refute claims that she’s overly secretive and legalistically clever.

For instance, she might have taken up the suggestion of Republican National Committee Chairman Reince Priebus, who demanded Clinton ask a neutral arbiter to review the contents of her private email server.

But Clinton didn’t.

She remained poised before a pack of reporters, giving no ground. The server will remain private. She said she had exercised her right to decide which of roughly 60,000 emails at issue were work-related and which concerned personal topics, such as her mother’s funeral and her daughter’s wedding. She deleted and did not archive those in the second group, she said.