A guided missile corrects its trajectory as it flies, homing in, say, on the heat of a jet plane's exhaust. A great improvement on a simple ballistic shell, it still cannot discriminate particular targets. It could not zero in on a designated New York skyscraper if launched from as far away as Boston.

If your plane is being hijacked by an armed man who, though prepared to take risks, presumably wants to go on living, there is room for bargaining.

Humans have a proven track record in taking over planes by the use of threats, which work because the legitimate pilots value their own lives and those of their passengers.

Richard Dawkins Quotes