The CDC study didn't examine the specific factors that account for the heavy burden of HIV among young black gay men, but the CDC has theories.

CNN: CDC: Blacks, gays at high risk for HIV infections

By their own account, many journalists began to examine the drone programme only in the later years of Mr Obama's first term.

BBC: Viewpoint: US media lax on drones

Facebook has accompanied the changes with new tools and has encouraged users to examine their account settings.

WSJ: Facebook Grapples With Privacy Issues