Nathan saw in this an opportunity and invited Shanker to speak at the Itasca Seminar. His goal was to hide his side’s privatization aims under the shadow of progressive unionism.     And it worked. In fact, if you look up the history of charter schools, you’ll STILL find people who insist they were invented by Shanker.     With this cover, the Citizen’s League, which was underwritten by the Minneapolis Foundation, was able to pass a bill requiring mandatory…