In this quote by Kurt Vonnegut, the speaker is confronted with the idea of writing a book to prevent wars, to which the suggestion of writing an "anti-glacier" book is made, implying that both are equally futile endeavors. This quote speaks to the pessimistic view that wars are inevitable and as unstoppable as glaciers.
The comparison between wars and glaciers suggests a sense of unchangeable, longstanding power and force. Glaciers are slow-moving, formidable natural phenomena that take incredible effort to alter or redirect. By equating wars to glaciers, Vonnegut emphasizes the difficulty in combating or preventing them. This quote hints at the complex, persistent nature of conflict and violence throughout history, suggesting that efforts to eradicate war may be as fruitless as trying to halt the advance of glaciers.