Here's what you metric guys still arguing in this thread need to do:
First, you call yourselves the 'mets'. Now, each one of you form your group of scientists, and instead of doing science, have them study the reasons behind the USA being metric, and then have these scientists form your "official" position. Modify their results to your liking, my assumption is that each one of you still arguing in here will be more or less like generals, but you'll need a leader, who will be known as "metroid prime", so you'll either have to pick one, or draw resistors.
Once your leader is picked and your beliefs on why the USA is not metric are formed, you can now spend your time trying to change things. Don't start with the USA though, first you have to cleanse yourselves of any nonbelievers. First, evangelize all the people of your land on the officially accepted reasons why the USA is not metric. Many will accept, but some will not, and these ones are heretics and you'll surely need to burn them. Or throw them in a body of water and see if they float. Once this is all taken care of, you're ready to move to phase 2.
You're going to need boats, air travel is too expensive nowadays and besides they aren't going to let you on a plane with those torches and pitchforks. Once you arrive in the USA, you'll need to systematically move from town to town, spreading the metric by force and burning all who refuse to accept, or more likely, simply do not understand why you're doing what you're doing and would rather be going about their business.
In the end, you can now have 100.00% of the world metric and you can then move on to the next thing that you want to argue about.