Why is .gov only for US government agencies?

[Matthew Petach <mpetach () netflight com>]

Wondering if some of the long-time list members
can shed some light on the question--why is the
.gov top level domain only for use by US
government agencies?  Where do other world
powers put their government agency domains?

With the exception of the cctlds, shouldn't the
top-level gtlds be generically open to anyone
regardless of borders?

Would love to get any info about the history
of the decision to make it US-only.

Thanks!

Matt