We'd love to say that "Shine, Perishing Republic" was inspired by Pink Floyd, but that would be a lie. Jeffers wrote this diamond back in 1925, so although we can't say he was planting the seed for a killer rock song, we can say that the poet and the band were working with a somewhat similar idea. We love when things look shiny and alluring and love them even more when they have the potential to inspire us to do great things. Even when a bright shiny thing looks as if it's dying, we can't help but hope it will come back and knock our socks off. So the poem's title is indicative of the more optimistic side of the speaker's ideas, the side that recognizes something about America that's not a decaying empire.
Speaking of optimism, what comes to mind when you hear the word "shine"? Do you feel inspired? Maybe a little rejuvenated or fresh as a morning daisy? Okay, maybe that's a bit overboard but at the very least the word "shine" probably sounds a little less depressing than a decaying fruit, right? It's fitting then that Jeffers would use this more uplifting line as the title of the poem, to kind of dissuade us from simply focusing on the not so happy parts of the poem. The speaker wants us to pay attention to the stuff he says about decay (he says it's perishing after all), but the bigger idea we're supposed to remember is that America's republic can still shine nonetheless. It's kind of like tough love. Sometimes you need to tell your friend that he's being a jerk for whatever reason but you tell him these things because you care. So the speaker wouldn't be getting into so much detail and concern over America's rotting empire if he didn't care about the republic he sees beneath it all. That shining title keeps us focused on the silver lining.