"Ahu" are stone platforms on which many moai sit. There are 313 known ahu and 125 of these carry moai. The biggest, Ahu Tongariki is 220 m (720 ft), and had the most (15) and tallest moai.
We can't gather the intelligence we need to foil future attacks, if we are blindly granting terrorists the right to remain silent. But for some reason, we've already done that - with the terrorist who tried to bring down Flight 253.