President Barack Obama summoned the Pentagon's leadership to the White House on Thursday for a crisis meeting about sexual assault in the armed forces, but the commander in chief said that "there's no silver bullet to solving this problem."

In a brief appearance after the session, Obama said sex crimes in the military are "dangerous to our national security" and "not a sideshow." He said military officials had told him that "they're ashamed by some of what's happened," and he pledged to work with Congress on legislation to address the issue.

Despite years of intensive effort to confront the problem, military commanders earlier admitted their collective failure in frank confessionals and seemed at a loss for answers.