Not sure of author, but obviously an homage to Kipling

As it happens, once our land
Was guaranteed the upper hand.
We ruled the seas from here to there
And landed armies everywhere.
The Kaiser, Hitler, Ho Chi Minh
No enemy could hope to win.
Our cities far from foreign shores,
Our people safe from far-off wars
Grew fat in their security
From sea to ever-shining sea.

And so it was we thought to share
Our good fortune as we could spare
The sacred seeds of liberty
Fallen from our blood-spattered tree.
We disregarded Europe's classes
And embraced the huddled masses
Come one, come all, out went the call
As hubris presages a fall,
For did not Man want to be free
And dwell in true equality?

German, Italian, Irish too,
Norwegian, Swedish, Dutch, and Jew,
They came to seek a better life
Escaping all that Old World strife.
And yet, they did not understand
The rights of every Englishman,
The Common Law was mystery
To grandchildren of serfs unfree.
And so they swore to flag and place
While seeking to transform the base.

Whatever happened, we had got
Atomic bombs, and they did not.
But then came Nineteen Sixty-Five
When sons of refugees contrived
To open doors to all the races
Black and brown and yellow faces.
Thus assured prosperity
We gave away technology,
We ruined universities
While lauding our diversities.

God was dead or so we heard
And Nation just a racist word
We learned a new and nobler truth
Built on a dream of vibrant youth
While our jobs sailed overseas
And went to new minorities.
Then aliens invaded schools
We realized that we'd been fools.
At last we saw the dreadful fact
Of copybook gods coming back.

Once we had the Maxim Gun
Whatever, so does everyone.
Now we live in exciting times
And pay the price for history's crimes.

So?