Magneto is the manifestation of the saying, "one man's terrorist is another man's freedom fighter." You could probably reasonably say:
Professor X : Magneto :: Dr. Martin Luther King, Jr. : Malcom X
Professor X and the X-Men were all for mutant equality, but they always favored peaceful acceptance. Conversely, Magneto recognized that large portions of society would never accept mutants. It also bears mentioning that Magneto carried some "racist" (for lack of a better word) tendencies towards non-mutants. In his view, non-mutants are lesser beings.