President Barack Obama said Friday that Sony Pictures “made a mistake” when it pulled its comedy The Interview in the face of threats by hackers who he said were from North Korea. He also vowed that the United States would respond to the cyberattack. Speaking at his year-end press conference, Obama said he was “sympathetic” to Sony’s situation. The company had just had its computer network sabotaged and huge amounts of internal data exposed, and the hackers who did it then threatened violence against theaters that showed the movie.