Oh, the humanity

May 6th, 1937, Lakehurst, New Jersey. The mighty German Zeppelin, the Hindenburg, is attempting a mooring. At that point it is certainly Nazi Germany's finest airship. This is not the airship's first trip, and friends and family are at Lakehurst waiting for the arrival of the zeppelin. Herb Morrison is there reporting. Morrison is also recording the event for later rebroadcast. As the zeppelin arrives, Morrison is describing the event - then suddenly, it bursts into flames. Morrison is shocked, but keeps talking though breaking occasionally overcome by the tragedy. It's stated that it is radio news at its finest, news events that are reported as they are happeneing. This event reflected what was to come with radio broadcasting immediately before and during World War II. The entire broadcast follows:

« Here it comes, ladies and gentlemen, and what a sight
it is, a thrilling one, just a marvellous sight. It is
coming down out of the sky pointed toward us, and
towards the mooring mast. The mighty diesel motors
roar, the propellers biting into the air and throwing
it back into gale-like whirlpools...

"No one wonders that this great floating palace can travel
through the air at such speed with these powerful
motors behind it. The sun is striking the windows of
the observation deck on the eastward side and sparkling
like glittering jewels against a background of black
velvet...

(...)

"It's burst into flames! Get this, Charlie, get this,
Charlie. Get out of the way, please, oh, my, this is
terrible, oh, my, get out of the way, please! It is
burning, bursting into flames and is falling on the
mooring mast and all the folks we... this is one of the
worst catastrophes in the world! Oh, it's four or five
hundred feet into the sky, it's a terrific crash,
ladies and gentlemen. (It's soaking in flames now)
Oh, the humanity! »

- Herbert Morrison, Lakehurst, New Jersey, May 6, 1937, 7:25 pm.
Oh, the emotion...

Herbert Morrison was working for WLS Chicago when he covered the Hindenburg fire at Lakehurst Naval Station on 6 May 1937. His famous rapid-fire description of the unfolding tragedy got him fired for being too emotional—despite the fact that NBC, which had had a strict policy against airing recordings, made its first-ever exception for him in what was also the nation's first coast-to-coast broadcast. Not surprisingly, he somehow managed to find work at NBC after his firing and have a respectable career as a radio reporter thereafter.

This expression, although it appears to have originated with a newscast during the explosion of the Hindenburg, is often taken out of context nowadays. It is generally used in an "ironic" or exaggerated tone, and it's likely that users don't know its history. Examples:

enkidu: I just wrote a script that will auto-node all the comments posted to slashdot in real time.
nate: Oh, the humanity!

"The Beatles' Revolution is being used in an ad for one of the largest corporations on the planet! Oh, the humanity!"

Real life example: The first match on Google for "oh the humanity" turns up a site reviewing bad movies.

The expression conveys that something truly disturbing has happened, although it doesn't necessarily have to do with humans or the loss of human life, and the speaker is being somewhat mocking and melodramatic.