When William “Wild Bill” Wellman replaced Archie Mayo as director, he reversed his male leads, and birthed the star of the actor whom fifty-five years later Cagney friend President Ronald Reagan eulogized as “one of America’s finest.” Described by Will Rogers as “a bunch of firecrackers going off all at once,” with limited previous screen experience James Cagney became Tom Powers, trading places with less than dynamic Edward Woods, who was thus switched to the tag-along secondary part of pal Matt Doyle. On the strength of the former Broadway dancer’s arrogant, “tough, hardboiled, cocksure” performance, The Public Enemy set the stage for his career and for the male-oriented dominant Prohibition era gangster genre, which offered some twenty-five films in that year of 1931 alone.

Under the recent Production Code, the film was not so graphically violent, how much less so compared to today’s splatter. It is fittingly shown in the Museum of Modern Art’s Modern Mondays celebration of eighty years of its Film Department, since it was one of the very first acquired for that invaluable collection.

There are too many slow or melodramatic longueurs, and overdone early-talkie acting, to consider the eighty-three minutes inspired. Beyond Tom’s ultra-famous mashing a breakfast grapefruit half into temporary girlfriend Kitty’s (Mae Clarke) face, based on actual Earl “Hymie” Weiss, who used an omelet -- cops-and-robbers was generally misogynistic, with, true to form, him walloping good-natured seductress Jane (Mia Marvin) for good measure -- it is still worth seeing not only for the star’s working up to Rocky Sullivan and Cody Jarrett, but also for what it says about the national frame of mind eight-and-a-half decades ago.

Coincidentally made at the time that cinema was gaining acceptance as a seventh art, Warners and Vitaphone’s hokey printed opening and closing messages are clear and point to the cult of the Irish cop on the corner, the G-man, the traumatized hero doughboy returned from the Great War “Over There,” and J. Edgar Hoover and his Bureau of Investigation (the “Federal” was added in 1935). The criminal-as-Godfather-etc. hero-with-a-code-of-ethics was at the time unthought of, and, more to the point, all of them die, as crime does not pay, full stop. “I ain’t so tough,” they come to realize, too late. The bad guy is Irish rather than Italian as in the more nuanced Scarface of a year later, a Capone take denounced by the Order of Sons of Italy in America. The gangster is not an individual man but “a type,” we are lectured in print, a parasite that, with good clean values, Authority will be able to eradicate, so no worry.

There is not much screen room for Tom’s stern police officer father (Purnell Pratt) but sympathy for simpering deluded Ma (Beryl Mercer) and, if not affection at least approval for stuffy war veteran brother Mike (Donald Cook). The younger sibling’s increasing violent brazenness will eventually turn off even boyhood chum-in-delinquency Matt, married by then and pushed by wife Mamie (Joan Blondell) to go straight, while sultry Texas blonde Gwen Allen (Jean Harlow) pushes Tom towards ever greater extravagance in crime and lifestyle with her prescient “Oh, Tommy, I could love you to death.”

Both boys (Frank Coghlan, Jr., plays the young, 1909 Tom) had begun by selling stolen anything to dandyish fence Putty Nose (Murray Kinnell), Tom’s ruthless murder of whom will prove the final straw for Matt. By 1917-20, they have graduated to Paddy Ryan’s (Robert E. O’Connor) gang, itself to be absorbed into the strong-arm bootleg enterprise of “Nails” Nathan (Leslie Fenton). Ma may anticipate Cody’s Ma Jarrett; and maybe the film killing of racehorse Rajah -- the death of real-life Samuel “Nails” Norton was avenged on a horse by friend Louis “Two Gun” Altieri -- inspired Puzo and Coppola; and the turf wars against the Schemer Burns boys were to be mirrored in many another ‘thirties film.

In spite of woodenness, creakiness in plot, and unintentional humor in printed piety, (and in some of the acting), The Public Enemy, a film of its time, was a sensation at that time, and is still not to be missed today.

(Released by Warner Bros. and not rated by MPAA.)