Which lines in this excerpt from W.B. Yeats's "An Irish Airman Foresees His Death" suggest that the speaker's choice to become an airman in the war was influenced by his perception of the futility of life?
1 (I know that I shall meet my fate
Somewhere among the clouds above;
Those that I fight I do not hate,
Those that I guard I do not love;)
My country is Kiltartan Cross,
My countrymen Kiltartan's poor,
2 (No likely end could bring them loss
Or leave them happier than before.)
Nor law, nor duty bade me fight,
Nor public men, nor cheering crowds,
3 (A lonely impulse of delight
Drove to this tumult in the clouds;)
I balanced all, brought all to mind,
4 (The years to come seemed waste of breath,
A waste of breath the years behind)
In balance with this life, this death.