Anything that ends in .gov is related to a government entity in the US. Other countries don’t get access to that TLD.

I'm not sure if understood correctly, but https://www.tsunami.gov/ works without any problems even from Europe, Poland.

The US government controls who gets .gov domain names, but the websites are available to anyone.

ah, you're right. I knew that, think I must've looked at it too fast and assumed it was .gov.ca. (which isn't even the TLD that the Canadian government uses, but never mind...)