Empire by Dar Williams lyrics below. Also, here is a Firefly video with the song used as a background.
Who's afraid of the sun?
Who would question the goodness of the mighty?
We who banish the threat,
When your little ones all go nighty nighty?
Well there's no time for doubt right now,
And less time to explain.
So get back on your horses,
Kiss my ring,
And join our next campaign,

And the Empire grows
with the news that we're winning,
With more fear to conquer,
more gold thread for spinning,
Till it's bright as the sun,
Shining on everyone.

Some would say that we've forced our words,
And we find that ingenuously churlish.
Words are just words.
Don't be so pessimistic, weak and girlish.
We like strong, happy people
Who don't think
there's something wrong with pride,
Work makes them free,
And we spread that freedom far and wide,

And the Empire grows the seeds of its glory,
For every five tanks,
Plant a sentimental story,

Till they worship the sun,
Even Christ loving ones.
And we'll kill the terrorizers
and a million of their races,

But when our people torture you,
that's a few random cases.
Don't question the sun.
It doesn't help anyone.

But the journalists cried out,
When it was too late to stop us.
Everyone had awakened
To the dream they could enter our colossus.
And now I'm right, yeah, you said I'm right,
There's nothing that can harm me,
Cause the sun never sets on my dungeons or my army,

And the Empire fell on its own shattered axis,
And the Emperor wanes as the silver moon waxes,
And the farmers will find old coins
In their strawberry fields,
While somebody somewhere twists his ring
And someone kneels.
Oh, where is the sun Shining for everyone?
Where is the sun Shining for everyone?