https://www.taxconnections.com/taxblog/relinquishment-the-us-exit-tax-and-the-confiscatory-case-of-non-u-s-pensions-u-s-pensions-avoid-this/
Relinquishment, The US Exit Tax And The Confiscatory Case Of NON-U.S. Pensions (U.S. Pensions Avoid This!)