You keep saying that's only in the US. That's wrong. 168 countries have signed on to the Berne Convention, a document stating that what is copyrighted in any signatory country will be considered copyrighted in all signatory countries. In fact a lot of what you're saying is totally wrong.
OP, please read below:
There are a few basic rights of copyright: reproduce (make a copy), create a derivative work, distribute, perform in public, and display in public.
Since any artistic creation is copyrighted as soon as it is put into tangible form (written down, recorded, built, what have you), the OP DOES have copyright. However, without paying the L.O.C. fee, there is no record of this copyright, which can be a hassle if things come to a lawsuit.
So, you already have the copyright on your work. However, if you want to take it a step further, you can pay the L.O.C. to obtain an official certificate of copyright - which will take about 3-6 months to get.
My advice is post it and make it clear that while you distribute it, others may NOT distribute it, publicly display it, or create a derivative work of it. If you wish, you can specify that they may make a copy for personal use.
Source: entertainment management graduate with real life experience obtaining copyrights.
