NEW YORK (AP) - For many black Americans, it's a conversation they find hard to avoid, revisiting old fears in the light of bright new hopes. They watch with wonder as Barack Obama moves ever closer to becoming America's first black president. And they ask themselves, their family, their friends: Is he at risk? Will he be safe? There is, of course, no sure answer. But interviews with blacks across the country, prominent and otherwise, suggest that lingering worries are outweighed by enthusiasm and determination. "You can't have lived through the civil rights movement and know something about the history...