Of course, _removing_ a feeling tube is "passive" whereas making a lethal injection is "active". 
 Why removing a tube is not considered active? This is an idiocy! (Obviously, you are rigt, Caesarion, that the Schiavo case was considered passive euthanasia and therefore allowed in the US, but I want to point that the law which allows letting someone die of thirst-hunger and forbidding a lethal injection is idiotic and monstruous).