Not American, what is the difference between CV and resume? I always assumed they were synonyms.
US resumes are ideally 1 page with 2 pages (IMHO) being acceptable if one has enough experience.
American CVs spell out everything with a length that scales linearly with experience. Every publication. Every role. Major projects. Awards. Etc. For long-time academics these can run over 10 pages. A recent PhD recipient might use 3-4 pages for a CV.
What if someone has 25 years of experience and held 10 different positions during that time, has a lot of ceritifications and other credentials? How do you fit all that on just two pages?