Answer:
The correct answer is regret for what no longer exists.
Explanation:
This question refers to the poem "For the Union Dead" by Robert Lowell.
What the author reflects in these lines, as well as in the rest of the poem, is regret for what no longer exists because of the civil war.
There are described in it, things that are no longer as they were before or that no longer exist, such as:
<em>"The bronze weathervane cod has lost half its scales."</em>
<em>"Parking spaces luxuriate like civic sandpiles in the heart of Boston."</em>
<em>"Two months after marching through Boston, half the regiment was dead"</em>
