NEW YORK (AP) — Some politicians carry threats to their livelihood in the palms of their hands. News stories in recent weeks about offensive or ill-advised text messages have blown up the careers of several young Republicans in a chat group, led a nominee for a White House job to drop out , threatened the campaign of a Democrat running for Virginia attorney general and embarrassed a federal prosecutor. Memories are still fresh of this spring’s inadvertent inclusion of a journalist on a Signal