WASHINGTON — The Motion Picture Assn., the international arm of the Motion Picture Assn. of America, has named Ken Jacobsen the new director of worldwide anti-piracy.Jacobsen, who joined the MPA in 1998 after a 28-year career in the FBI, replaces Ric Hirsch. The anti-piracy arena is increasingly important at the MPAA and other trade groups such as the Recording Industry Assn. of America that represent copyright-rich industries. Although Hollywood has embraced the Internet age, it is wary of pirates who use computers and the Web to traffic in bootlegged material. “Protecting member company product in the digital era is one of the greatest challenges our industry has ever faced,” said MPA and MPAA topper Jack Valenti.