Does it have to be a one-time living, breathing icon? If not, then surely Number One would be Mickey Mouse (with Snoopy perhaps Number Two).
And surely Bing Crosby, who was a prominent cultural figure in the 1930's, 1940's, 1950's, 1960's and 1970's, should be on that list. Ditto Sinatra, who was a major star from the 1940's to the 1980's.
Laurel & Hardy. Major stars in both silent pictures (which were easier to distribute internationally because the title cards could just be replaced with whatever language was needed) and talking pictures (they even shot foreign language versions of some of their short films for French and Spanish markets) and their images are still instantly identifiable today, even to people who may never have seen one of their films.
Bob Dylan must be included on any such list.
Shouldn't that be Joe DiMaggio then?