Let ignore the blunt, and very true, jab at my country for a minute.
The point of only allowing users to vote is to reduce the amount of trolls that can abuse the system, however that won't solve the problem. One idea that I can think of is to only allow users with so many posts to vote, lets say 75 for now. Of course there can be exceptions made for people that are well known and help the forums however they can. I doubt that someone who is only using the system to troll would take the time to get a high post count. Just my thoughts on this.