You actually make a good point. The analogy gets used a lot because big ships do have big turning radiuses. But the better analogy is probably something more along the lines of the captain gives an order and various groups within the ship don't really agree with the order, so they say they're doing their part to make the ship turn but they're really not. Maybe the rudder have been moved a bit but the propellers are acting against the change. Furthermore, some percentage of the crew has decided that the ship should really be a plane and that's what they're working on.
Not really. On a ship (i.e. naval vessel), if the subordinates don't obey the commands, they get sent to prison for mutiny.
In a big organization, if the CEO says to do something (i.e. new vision... PKI's!), most people can ignore it with little chance of reprisal. It's much more of a political/social hierarchy than a military one.
