Copyright protection rules are fairly similar worldwide, due to several international copyright treaties, the most important of which is the Berne Convention. Under this treaty, all member countries -- and there are more than 100, including virtually all industrialized nations -- must afford copyright protection to authors who are nationals of any member country.
All countries in the Berne Convention must offer copyright protection that lasts for at least the life of the author plus 50 years, and must be automatic without the need for the author to take any legal steps to preserve the copyright.
In addition to the Berne Convention, the GATT (General Agreement on Tariffs and Trade) treaty contains a number of provisions that affect copyright protection in signatory countries.
Together, the Berne Copyright Convention and the GATT treaty allow U.S. authors to enforce their copyrights in most industrialized nations, and allow the nationals of those nations to enforce their copyrights in the United States.