Cummings was a poet who had experienced war at first hand in World War 1, having served as a volunteer in the Ambulance corps in 1917, as well as being drafted into the regular army in 1918. While working in Paris in 1917, Cummings (with his friend John Dos Passos) was accused of espionage and imprisoned by the French authorities because of his freely expressed anti-war views, and what was seen to be his suspiciously friendly relationships with German soldiers. This poem reflects some of the views that Cummings held on jingoistic speechmaking--though it's hard to tie it down to a specific occasion. Some interesting critical views on the poem can be found at Modern American Poetry
The first thing you do when looking at a poem is, of course to count the lines--and lo! there are 14! Yes indeed, although at first sight this looks like an incoherent speech randomly broken up into lines (even in the middle of a word) it is, of course, a cunningly contrived sonnet. The rhyming scheme is that of a Petrarchan, or Italian sonnet, with an octet which rhymes ABABCDCD and a sestet which, unusually, rhymes EFGFEG. As does a traditional sonnet, you could say that this poem asks a question or proposed a problem--but in this case the problem is inherent in the attitude and in the voice of the speaker, and the solution is not obvious, except inasmuch as the final line distances the poet from the ideas and manner presented. When looking for a 'turn', it would be possible to say that there is one where you might expect it, at line 9, where the trivial jingoism takes on a more serious tone, or (as in a Shakespearean sonnet) at the very end, where the contrast between 'shall the voice of liberty be mute' and the speaker's stagy self-refreshment points up the artificiality and lack of authenticity of the views he expresses.
Cumming's trademark lack of punctuation and capitalisation emphasises this sense that the poem is a stream-of-consciousness speech full of cliches. He juxtaposes phrases which have huge resonance for an American reader such as 'land of the pilgrims' with vague language such as 'and so forth', 'of course', 'what of it' which seem to undermine these powerful connotations, and make it seem as though the speaker thinks of them as meaningless. This is accentuated by the unfinished phrases. Cummings takes the starting line from the American National Anthem (the star-spangled banner), but leaves it unfinished, splicing it to the first line of the song 'My Country 'tis of thee', which was used as the unofficial national anthem before 'The Star-Spangled banner' was officially adopted, so that they become one less meaningful, vaguely patriotic jumble: 'oh say can you see by the dawn's early my/ country tis of', a jumble accentuated by the remembered rhyme between 'my' and the missing word 'light'.
The casual 'next to of course god' in the first line of the poem implies that God is taken for granted (though not, as is conventional, capitalised, any more than is the name of the apparently revered country) suggesting that both are tokens and not realities. The casual colloquialisms that litter the poem seem to imply a lack of precision and sincerity throughout (particularly notable in the run-together 'even deafanddumb'). The long list of euphemisms for the name of God used instead of 'swearing' become a jumble of insincerity, separated neither by commas nor by conjunctions: 'by gorry/ by jingo.by gee by gosh by gum'--a strategy you will remember which is called asyndeton. The effect created here is of someone trying to press all the right patriotic buttons, but not actually producing anything very convincing--either through laziness, or through underestimating the intelligence of his audience (which is us, dear reader). The tone is cynical, as though all these patriotic ideas are produced only for effect and are not believed in: 'what of it we should worry'--the epitome of the 'I'm all right Jack' philosophy
In line 9, there is something of a turn, as the speaker's rhetoric seems to become momentarily more coherent and more dangerous. The 'why talk of beauty' line seems to respond to an imagined audience response, and pulls out all the rhetorical stops in terms of cliche, referring to 'these heroic happy dead' in ways which might remind us of WW1 poets such as Rupert Brooke. Look for instance at Brooke's sonnet 'The Dead', which starts: Blow out, you bugles, over the rich Dead!/There’s none of these so lonely and poor of old, /But, dying, has made us rarer gifts than gold '. Other aspects of these sestet lines might remind us of WW1 as well--the image of lions 'who rushed...to the roaring slaughter' reminds me of this poster (see left) urging the colonial countries to come to England's aid: There is an ambiguity about the dead seen as lions--for as they have died, surely they have been slaughtered rather than slaughtered others (perhaps the image also owes something to big-game hunting which was popular at the time of writing with contemporary writers such as Hemingway).
The final message seems to be 'they did not stop to think they died instead'--like those in 'flag' who can 'blind their conscience', here lack or thought or reflection seems to be presented as something advantageous for a country in its soldiers. Reminds us also perhaps of 'The Charge of the Light Brigade' with 'theirs not to reason why'. The ironic juxtaposition of this with 'then shall the voice of liberty be mute?' emphasises just how far the voice of liberty is smothered by this kind of rhetoric. Here the individual soldier is silenced in favour of the voice of the politician, who we are sharply reminded is on a podium, drinking a glass of water, a momentarily dry throat the only risk that his speech involves him in.
As refreshment after that poem, you should probably watch this video of the greatest speech ever made--by Charlie Chaplin in 'The Great Dictator'.