In my group the only guys who get interviewed are the ones who write stuff like, drink 12 beers every day, performed strategic default on mortgage, interaction with foreign nationals other issues requiring additional info. Trigger in those cases is the need for clarification. I had an exchange student from China last year and was a bit worried, consulted my security manager prior to doing it. E-QIP (or whatever the new name is) has a section just for exchange students, but it required me to get a bunch of info from my student.
To answer the OP question...The one guy I work with who is married to a naturalized citizen gets interviewed regularly. Don't sweat it, be honest