[1] As in the case with .gov, the United States is the only country that has a top-level domain for its military, a direct result of the United States' military's role in the creation of the Internet.
Other countries often use second-level domains for this purpose, e.g., mod.uk for the United Kingdom's Ministry of Defence.
Canada uses norad.mil with the United States as they jointly operate the North American Aerospace Defense Command.
The official athletic program sites of the three academies that are members of NCAA Division I (Army, Navy, Air Force) use com domains, as well as Coast Guard, which is a member of NCAA Division III.
The United States Coast Guard, like other military services, uses the mil domain, although during statutory peacetime the service falls under the United States Department of Homeland Security.