P.S. A friend provided a link to a negative review of 'Gatekeepers' that appeared at http://www.ynetnews.com/articles/0,7340,L-4348449,00.html
In my view the argument is breathtakingly nonsensical; i.e., that the Shabak directors suffer from some sort of reverse Stockholm syndrome. If that's the best attack its opponents can come up with, then the film is even more powerful than I thought.
More links to negative reviews are welcome.