What's Brooke's attitude towards the war in "The Old Vicarage, Grantchester"? What's the theme of this poem?

"The Old Vicarage, Grantchester" by Rupert Brooke plays with the genre of the traditional pastoral, adding some elements of humor, while still conveying a traveler's longing for the peaceful environment of his home. There is no obvious war theme in the poem, as it was actually written before the outbreak of World War I. It does display attitudes of anti-Semitism, misogyny, and xenophobia, as well as class prejudice, all components of Brooke's sense of patriotism.

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"The Old Vicarage, Grantchester" by Rupert Brooke plays with the genre of the traditional pastoral, adding some elements of humor, while still conveying a traveler's longing for the peaceful environment of his home. There is no obvious war theme in the poem, as it was actually written before the outbreak of World War I. It does display attitudes of anti-Semitism, misogyny, and xenophobia, as well as class prejudice, all components of Brooke's sense of patriotism.

Grantchester is a small village outside the great university town of Cambridge. It is approximately a one to two hour walk from Cambridge, along a scenic footpath. Students, professors, and tourists often walk down from Cambridge to Grantchester for tea on weekend afternoons in warm weather and it is a favored place for well-off Cambridge professors to retire. Brooke and his circle often visited Grantchester, where they engaged in various sexual exploits; the nostalgia here has a rather decadent subtext if one reads it in light of Brooke's biography.

In this poem, Brooke draws a parallel to people in the busy town of Cambridge taking refuge in Grantchester with himself dreaming of his home in England while traveling abroad. His brief description of the contrast between his situation as a traveler and the beauties of home appear in the lines: 

Here am I, sweating, sick, and hot, ...

...Temperamentvoll German Jews

Drink beer around ...

His nostalgia for England seems balanced with hatred of Germany and anti-Semitism. One could argue that he would see war as a defense of this idyllic setting of Grantchester and the peaceful pastoral setting as something that would be lost in the war, but it is not certain that when he wrote this poem he was writing with that sort of foresight.