On July 19, 2019 the IRS announced six new compliance initiatives.
Of particular interest to U.S. citizens and permanent residents (Green Card holders) is what is described as:
U.S. citizens and long-term residents (lawful permanent residents in eight out of the last 15 taxable years) who expatriated on or after June 17, 2008, may not have met their filing requirements or tax obligations. The Internal Revenue Service will address noncompliance through a variety of treatment streams, including outreach, soft letters, and examination.
What is expatriation?