Museums are culturally influential, but the space inside them is tight. Not everything fits, so choices must be made.

In the old days, the stories that museums picked to tell weren’t questioned too much. Lately doors have been opened to different kinds of stories, changing our perceptions of the types of material that fit into the citadel of high culture. When done right, it makes the institutions feel roomier than ever, not cramped.

“Soft Power,” at the San Francisco Museum of Modern Art through mid-February, epitomizes its era in that it looks self-consciously at the ways in which cultural influence is exerted, with special attention to previously hidden voices.

“The title is a twist on the Reagan-era phrase,” said Eungie Joo , the museum’s curator of contemporary art, who conceived the show.