> what's the deal with making the distinction between domestic mass surveillance and foreign mass surveillance? Are there no democracies aside from the US?

I think it's just saying that spying on another country's citizens isn't fundamentally undemocratic (even if that other country happens to be a democracy) because they're not your citizens and therefore you don't govern them. Spying on your own citizens opens all sorts of nefarious avenues that spying on another country's citizens does not.