Watershed Moment By Caitlin DeSilvey History Lesson Posted Thursday, April 17, 2008, at 7:13 AM Tweet Want more of your favorite content on the MSN homepage? Try the news, sports or entertainment editons. Tweet MYSLATE Save this story. Follow all History Lesson articles. Follow the News and Politics section. Follow stories by Caitlin DeSilvey. MySlate is a new tool that lets you track your favorite parts of Slate. You can follow authors and sections, track comment threads you're interested in, and more. Click here to load comments.