While they have every right to be displaying their ignorance for the world to see... If I ever saw those people in real life, I'd spray them with a super-soaker.
As for the "Thank God for 9-11"... WTF? I MEAN WHAT THE FUCKING FUCK?!
September 11th was a tragedy caused by the hands of man, not an act of punishment by a deity. All it took was some people who believed strongly enough in their religion that they felt outsiders were infidels whom were unworthy to live. Throughout history, religion has been the motivator for the bloodiest battles humankind has ever seen.
The men and women who lost their lives on September 11th were not infidels, they were not warriors in a battle. They were American citizens like you and I, just expecting a usual day of work when their lives were tragically cut short. There is no justification for the horrible act taken against them.
It doesn't say much for your religion if you believe your deity condones acts of terror against your home country.