I agree that this is almost certainly bullsh*t, but I have to throw out the suggestion that possibly they are only talking about deflecting or steering a storm away from heavily-populated areas. It takes a lot less energy to dig a channel for a boulder rolling down hill to follow than to build a brick wall capable of stopping it cold. And of course, like any good American it is easy for me to then make the jump to weaponizing the damn thing - if you can steer it, maybe you can point it at your enemies (not that I have anyone in mind, President Chavez)...