And so, he concludes that his future holds little of value.  
The speaker notes that his "tumult"uous actions were driven by "a lonely impulse of delight," not by law or duty, or politicians or cheering crowds. In fact, he has little stake in the conflict around him--"Those that I fight I do not hate,/ Those that I guard I do not love." No possible ending to the conflict could bring his Kiltartan countrymen any more loss or any more happiness than they already enjoy. And so, he concludes that his future holds little of value.  FTP, name this poem by William Butler Yeats about an aviator who "know[s] that [he] shall meet [his] fate/Somewhere among the clouds above."
The speaker notes that his "tumult"uous actions were driven by "a lonely impulse of delight," not by law or duty, or politicians or cheering crowds.
An Irish Airman Foresees His Death