Dave Bonta looks at the New York skyline and sees something darker than a famous view. The towers become a "forest of glass stumps," a place where the trees have already been cut down. They are also an "over-crowded graveyard," where "any damn stone will serve" as a marker. The skyline starts to look less like a triumph and more like a crowded field of monuments to the dead.
The parenthetical lines work like muttered asides. They hint at a single man, maybe a powerful builder or tycoon, who lived off the city the way an epiphyte lives on a tree. His "dust" ends up "taking root in a million lungs," so his legacy is something people literally breathe in. That image is unsettling, and it suggests the poem's idea of ambition as a kind of pollution.
The speaker's tone is bitter and wry. The last stanza turns it into a quiet shrug of disbelief: it is strange what we have taught ourselves to find inspiring. The mood is sardonic and a little weary.