Noncompliant US taxpayers living abroad are getting nervous. If an informant seeking a hefty IRS reward, or FATCA doesn’t rat them out first, then the State Department will. This can happen when the noncompliant taxpayer renews his US passport.
Traditionally, the functions of the US Treasury and the Department of State were completely separate. However, we are seeing a continued erosion of this distinction as troubling economic times continue. The US passport renewal form mandates that the applicant supply his Social Security Number (SSN) if he has one. http://www.state.gov/documents/organization/79960.pdf
Read more here: