I think that was what they were going for - there are a few other comments like "trust only me" and "make sure to record everything that happens in this room" that were obviously foreshadowing the later years of Nixon's presidency. I love it when Doctor Who plays with the more subtle details of history like that, rather than always doing 'okay we went to space because aliens made us do it' and other big things.

I didn't even think of that! Oh man, Canton/Secret Service guy OTP, for serious.