Vice President Joe Biden said Thursday he was unsure if he will seek the Democratic presidential nomination, telling a Jewish audience that his decision will hinge on whether he and his family have the “emotional energy to run.” “Unless I can go to my party and the American people and say that I am able to devote my whole heart and my whole soul to this endeavor, it would not be appropriate,” Biden said, responding to a question following a foreign policy address. Biden offered his most extensive public remarks regarding his deliberations about entering a Democratic primary race that...