Another kind of explanation

From Joan Didion's collected essays, I find this:

I remember one trip home, when I sat alone on a night jet from New York and read over and over some lines from a W. S. Merwin poem I had come across in a magazine, a poem about a man who had been a long time in another country and knew that he must go home:

...But it should be
Soon. Already I defend hotly
Certain of our indefensible faults,
Resent being reminded; already in my mind
Our language becomes freighted with a richness
No common tongue could offer, while the mountains
Are like nowhere on earth, and the wide rivers.

- From "Notes from a Native Daughter", in Slouching Towards Bethlehem.

If anyone can find the Merwin poem, I would be grateful.