Two weeks ago, the National Post and I were served with a notice of libel by the Canadian branch of the Council on American Islamic Relations, or CAIR. The Post and I are not alone. Over the past year, CAIR's Canadian and U.S. branches have served similar libel notices on half a dozen other individuals and organizations in the United States and Canada. Each case has its own particular facts, yet they are linked by a common theme: That we defendants have accused CAIR (in the words of the notice served on me) of being "an unscrupulous, Islamist, extremist sympathetic...