[gambiting]

....how does seeing energy.gov help?

Even if you know that only US agencies use .gov, it's not like an American agency wouldn't publish a report on a worldwide trend, is it?

[junon]

Generally no, the government isn't an academic body. .gov sites tend to focus on the American people almost exclusively.

This isn't a rule by any means but seeing .gov usually translates to "pertains to the US"