It's pretty common to ask candidates for something new in their op-ed pieces before a publisher will run them and distribute them for free to millions of readers. All editors exercise that kind of control over op-ed pieces. If there is nothing new, then they don't want to waste the page on it. It doesn't infringe McCain's freedom of speech to not run his article for free in the paper. He can publish his ideas on his own, or he can take out an ad, or he can provide an article interesting enough to run. That was probably the biggest problem with it if McCain wrote it --- it was probably boring...