Again, emotions, not intelligence.
The flash presentation is a series of rapid images, devoid of context and definition. A purely perceptual thing, not unlike a TV commercial.
Makes you feel a certain way. Doesn't transmit a lot of information.
After all, once you get into the details, it isn't that simple. From their website:
The Stop the Clash campaign challenges the growing belief that fundamental divides between the "West" and "Islam" (whatever they actually mean...) make conflict inevitable.
The "whatever they actually mean" tells you all you need to know.