Filmmakers sometimes make remarks that ignore political and social sensitivities. We must remind ourselves that we are artists, not politicos. That is unless, you are a politico filmmaker (e.g., Michael Moore, Morgan Spurlock). Our job is to entertain, inspire, inform, and educate. In that order. Well, Cannes declared Lars von Trier a persona non grata at its festival amid his inflammatory comments surrounding Hitler. He may have had the right to say it, but he probably should not sympathize with the Nazi Leader, especially in France. Or anywhere in Europe for that matter. Don't worry about von Trier as he will most likely bounce back from this in a few years.
In case the phrase is new to you, persona non grata status is usually reserved in the political arena. Basically, it means "unwelcome person". In some countries, declared personas non grata will be prosecuted if caught trying to reenter that country. Talk about visiting those Latin lessons!