When I read the opening paragraph, what was running through my mind was Rudyard Kipling's 1898 poem, "Recessional". It was written at the time of Queen Victoria's Diamond Jubilee, celebrating her sixtieth year on the British throne and also celebrating the British Empire, which was then at its zenith.

The poem is too long to be quoted in full here -- see https://www.poetryfoundation.org/poems-and-poets/poems/detail/46780 if you like -- but it has lines such as

Far-called, our navies melt away;
   On dune and headland sinks the fire:
Lo, all our pomp of yesterday
   Is one with Nineveh and Tyre! 


To say that the US "would always be 'the one indispensable nation in world affairs'" is answered by the last two lines of "Recessional":

For frantic boast and foolish word—
Thy mercy on Thy People, Lord!