Maybe it's a pity Flanders and Swann never got round new words for a few National Anthems. But here's what they did write a propos some of the matters touched on in this thread (From this excelent website I found when I went looking for this song):

A Song of Patriotic Prejudice

The English, the English, the English are best
I wouldn't give tuppence for all of the rest.

The rottenest bits of these islands of ours
We've left in the hands of three unfriendly powers
Examine the Irishman, Welshman or Scot
You'll find he's a stinker, as likely as not.

The Scotsman is mean, as we're all well aware
And bony and blotchy and covered with hair
He eats salty porridge, he works all the day
And he hasn't got bishops to show him the way!

The English, the English, the English are best
I wouldn't give tuppence for all of the rest.

The Irishman now our contempt is beneath
He sleepes in his boots and he lies through his teeth
He blows up policemen, or so I have heard
And blames it on Cromwell and William the Third!

The English are noble, the English are nice,
And worth any other at double the price

The Welshman's dishonest and cheats when he can
And little and dark, more like monkey than man
He works underground with a lamp in his hat
And he sings far too loud, far too often, and flat!

And crossing the Channel, one cannot say much
Of French and the Spanish, the anish or Dutch
The Germans are German, the Russians are red,
And the Greeks and Italians eat garlic in bed!

The English are moral, the English are good
And clever and modest and misunderstood.

And all the world over, each nation's the same
They've simply no notion of playing the game
They argue with umpires, they cheer when they've won
And they practice beforehand which ruins the fun!

The English, the English, the English are best
So up with the English and down with the rest.

It's not that they're wicked or natuarally bad
It's knowing they're foreign that makes them so mad!

For the English are all that a nation should be,
And the flower of the English are Donald (Michael)
Donald (Michael) and Me!

(Perhaps fortunately the song never got round to discussing the Americans...)