Thanks for the in-depth response. My parents came out of Depression/WW II and acted like characters in a Capra. It was "that would be swell!" and "a fella like that deserves a licking" around the house. I believe Stewart was my father's role model, both from PA, flew bombers in WW II, carried themselves w similar "aw shucks" virtue.
1) An interesting Capra is "Meet John Doe" which is more or less the political situation we face today...we are so easily exploited, yet "Love Thy Neighbor" is almost the solution to everything, if we can make it stick.
2) As in most Capra movies, male and female protagonists start out jaded, subsequently place each other in "Hey wait! Together we can be David against Goliath!" mode (which probably won't work, but is quite sexy). A great relationship often borrows from cinematic "suspension of disbelief". Not sure if the ambition fuels the love, vice-versa, or simultaneously, but delicious "love conquers all" parables. I didn't really like Stanwyck, Arthur, or Reed originally, but after Capra, I'm sold!
3) I'm going to go on a limb here and declare that the Capra canon is the Beatitudes "what would Jesus do", end of story. No need for prayers, hymns, scripture, "Hallelujahs", simply watch these films over and over. They embody the service, humility, love, and "truth to power" that we're meant to utilize.
4) Interesting how we don't really know the political leanings of a Capra hero, its as though they are generic Americans, standing up for the little guy, yet not wanting to give any "free rides" (see Longfellow Deeds). Writer Robert Riskin deserves much credit for the Capra-esque invention (later used by Preston Sturges?) Honestly, much Jewish infusion there.
5) Have you ever reviewed the somewhat twisted Jesus parable "The Fountainhead"? Is this comic-book Nietzsche? Capra meets Milton Friedman? Jesus dynamiting the Pharisees?