Charter school teachers in Chicago are in their fourth day of a strike.   Yet I wonder why the leaders of the charter movement are quiet.   Where is Peter Cunningham of the Education Post?   Where is Shaver Jeffries of Democrats for Education Reform?   Not a word from Campbell Brown or Michelle Rhee?   Nothing from Bill Gates, Cory Booker, Barack Obama or Hillary Clinton?   Not a peep from Betsy DeVos or Donald Trump?   This…