The general synopsis is that the director is trying to paint of view of radical Muslims that connects them to the Nazi's of the 1930s, not through direct association, but through common themes, such as anti-semitism, the use of propaganda, and the fact that they both... umm... hate Americans and their freedoms? The director could have made a comparison to the Crusaders of the 12th and 13th centuries, but as a majority of the audience he is trying to target is likely Christian, the point would likely be lost. After all, let he who is without sin cast the first stone, yes?
Unfortunately, focusing on the idea of propaganda, this film seems to be more of propagandistic than documentation, grouping all of Islam into a category of radically hateful people, but stating as a disclaimer that they're really only talking about 15% of the Muslim population. This film promotes the idea that Americans should be scared of Muslims, that they should be scared, give the government more power to fight the good fight against these crazy Crusaders of the Star and Moon. This is not a good state to be in, because it causes citizens to be complacent with the freedoms and rights that are being taken away from them under the veil of "fear" and "protection". The population must not be sold on these ideals. Instead, citizens must, objectively and with an open mind, have the courage to seek the real truth, to throw out films like this and see what's really going on.
If you want to see a more accurate view of terrorism and fear (i.e. what to actually be afraid of), watch Alex Jones's "Terror Storm".