"But the SIS are more sorta CIA, except in a totally non-spying-on-other-countries-way."
Ahh, we do our fair share of spying actually.

"I think our equivalent of the Secret Service are those dudes who were looking after Don Brash, the Source of All Evil, and Deborah Coddington because Roger Kerr was hitting on her. So really, they can't have very much to do."
That's the Diplomatic Protection Squad, and they obviously have more to do than the US Secret Service!