Yes to both, Olli: Vito was contemptuous of Michael's "miracles performed for strangers," and of the fact that he had an "American" (not Italian, not Catholic) girlfriend. I don't think he was being critical of America--just critical of Michael's choices that so obviously rejected his family's values and his father's plans for him. In the flashback at the end of II, Tom refers to those plans, and the arrangements Vito made to keep Michael from being drafted (a one-year draft lottery was in effect before Pearl Harbor).