Although he rarely gave interviews and never held elected office, Santamaria became widely known through his regular commentaries in the Australian and in his magazine News Weekly.

Building on his battle against Communist influence in the trade unions, Santamaria boldly attempted to capture the ALP and transform it into a European-style Christian Democrat party. The ensuing split was disastrous, demoralising the ALP, and casting Santamaria out of the Labor fold for all time.