On February 16, 1943 Himmler issued a secret order to destroy the Warsaw ghetto. According to Himmler:
An overall plan for the razing of the ghetto is to be submitted to me. In any case we must achieve the disappearance from sight of the living-space for 500,000 sub-humans (Untermenschen) that has existed up to now, but could never be suitable for Germans, and reduce the size of this city of millions – Warsaw – which has always been a center of corruption and revolt.
The Nazis earmarked April 19, 1943 as the day they would close the Warsaw Jewish Quarter. As the ghetto burned, Jews were rounded up and sent to their deaths.
But people inside the ghetto - who sensed total annihilation was about to happen - planned to resist. As Goebbels noted in his diary: "The Jews have actually succeeded in putting the ghetto in a condition to defend itself."
And that resistance would prove to be much more costly - and deadly - to the Nazis than Himmler could have ever imagined.