This Frontline report has been fully absorbed and chewed over, but Donald Trump almost certainly decided to run for president after President Obama kicked him around — okay, humiliated him — during a 2011 White House Correspondents Dinner. Helen Lewis, deputy editor of the New Statesman, told Frontline (or somebody) this was what did it. From this point on Trump was determined to have revenge. Those present at the event said Trump “looked furious” as Obama sliced and diced him. New Yorker writer Adam Gopnik said, “His head set in place, like a man in a pillory, he barely moved or altered his expression as wave after wave of laughter struck him. There was not a trace of feigned good humor.” Please — watch the first six minutes. Just the first six. (Thanks to producer-editor David Scott Smith for calling attention.)