What do you think about Economic Unions?

We have seen that in as little as 50 years europe has become the european union (economically) and are enjoying Prosperity. But does any one know what the plans are for the 3 other areas of the world to make their own economic unions? The U.S., Canada and Mexico are talking about a North America Union. It seems a little scary, kind of like a one world government. Is this just another sign of the end of days?