
"A new king rose over Egypt, who did not know Joseph, and he said to his nation: 'Behold! The nation of the Children of Israel is greater and mightier than us. Come, let us deal cunningly with it, lest it become greater yet and, in the event of war, it too will join our enemies in fighting against us and will go up from the land.' ...And the king of Egypt said to the Hebrew midwives... 'When you deliver the Hebrew women, you will see the birthstones; if he is a son, you shall put him to death, and if she is a daughter, she will live.' But the midwives feared God, and they did not do as the king of Egypt had spoken to them, but they kept the boys alive. So the king of Egypt summoned the midwives and he said to them: 'Why have you done this thing and kept the boys alive?' And the midwives said to Pharaoh: 'For the Hebrew [women] are not like the Egyptian women; for they are lively. Before 
Why in the world would any leader ever enact a decree of genocide against his own nation?
the midwife comes to them, they give birth.' ...And Pharaoh commanded all his nation saying: 'Every son who is born shall you cast into the river, and every daughter you shall save alive.'" (Exodus 1:8-22)
There is a vast difference between Pharaoh's two decrees of genocide, a difference that is so glaring that few people ever notice it: in his first decree, Pharaoh "said to the Hebrew midwives [and only to the Hebrew midwives]... 'When you deliver the Hebrew women [and only the Hebrew women], you will see the birthstones; if he is a son, you shall put him to death, and if she is a daughter, she will live.'" In his second decree, "Pharaoh commanded all his nation [not only the Jews] saying: 'Every son [not only the Jewish baby boys] who is born shall you cast into the river, and every daughter you shall save alive.'"
The decree of a madman! Why in the world would any leader ever enact a decree of genocide against his own nation? The Midrash explains: "Why did he decree even against his own nation? His astrologers told him: 'The mother of the saviour of Israel is now pregnant with him, but we do not know if he will be a Jew or an Egyptian.' So immediately, Pharaoh gathered all the Egyptians and said to them: 'Give me your sons for the next nine months for me to throw into the River Nile.' ...And why did they decree that the boys be thrown into the River Nile? Because the astrologers could see that the saviour of Israel would meet his downfall through water, so they assumed that he would drown in water. In fact, death [in the Sinai Desert] would one day be decreed upon him as a result of the events of a well of water ." (Exodus Rabbah 1:18; compare Tanhuma, Vayak'hel 4)
With retrospect, we can understand the astrologers' confusion over the identity of Israel's saviour: Moshe was both Israelite and Egyptian, a Hebrew of the priestly caste and an Egyptian prince. Harder to understand is Pharaoh's response: in order to prevent the Jews from leaving Egypt, he was willing to slaughter untold numbers of his own people. Let us put this response in starker relief yet: Pharaoh's expressed concern was that the Jews would eventually outnumber the Egyptians, and in the event of war they would defeat the Egyptians. And in response, he decimated his own male population, ensuring that eighteen or twenty years henceforth, he would have no new soldiers at all.
But in his determination to prevent the Jews' salvation, he was willing to lead himself and his own people into mortal danger.
And eighty years later, when Moshe would demand of a later pharaoh that the Jews be released from their slavery, the Egyptians were willing to bring calamity upon themselves in order to prevent the Jews from being released. This is especially clear with the first three plagues, those of blood, frogs and lice: in each case, the Egyptian magicians, in a desperate attempt to prove that their magic was a match for Moshe's miracles, mimicked what Moshe had done. When the River Nile turned to blood, "the Egyptian magicians did likewise with their magic" (Exodus 7:22). Similarly when Egypt was smitten with frogs, "the magicians did likewise with their magic, bringing the frogs up over the land of Egypt" (8:3). And when they were smitten with lice, "the magicians did likewise with their magic, bringing forth the lice, but they were unable to" (8:14). That is to say, they were willing to add to their own plagues in their attempts to discredit Moshe.
Even when Pharaoh's servants had finally recognized that they would never defeat Moshe and his nation, and wanted to get rid of them, challenging Pharaoh directly with the words, "Do you knot yet know that Egypt is 
The Germans were willing to condemn themselves to military defeat, to destruction, just in order to murder a few more Jews.
lost?" (10:7), Pharaoh still refused to let them go. Pharaoh thus created the paradigm: the invariable rule of history is that all those who wish to destroy us are so consumed with hatred for us that they are willing to destroy themselves in order to harm us.
Shortly after the final plague, when we had just left Egypt, Amalek encountered us in the desert and attacked us; "and it happened that whenever Moshe would raise his hand, Israel would prevail; and whenever he would rest his hand, Amalek would prevail. But Moshe's hands were heavy, so they took a stone and put it beneath him and he sat upon it, and Aaron and Hur supported his hands." (Exodus 17:11-12) There is an obvious question here: When Amalek saw Israel prevailing, why did they not simply break off contact? After all, in this desert skirmish, far from inhabited land and with no resources at stake, Amalek had nothing material to fight for. But the Pharaonic precedent held true: Amalek was willing to fight to his own death in order to slaughter another few Jews.
Almost a thousand years later, when Amalek's descendant Haman wished to destroy us, he, too, was given fair warning: "His wise men and Zeresh his wife said to him: If Mordechai, before whom you have already started to fall, is from the seed of the Jews, you will not overcome him; rather, you will certainly fall before him." (Esther 6:13) But Haman, consumed with his hatred for Jews, went ahead and built the gallows upon which he himself and his ten sons would later be hanged.
This paradigm has held throughout our history. A generation ago we lived through the most vicious attempt ever to exterminate us all; and in the final year and a half of the Second World War, when Germany needed every man and every bullet on the front lines to defend their homeland, they still gave top priority to murdering Jews. Soldiers under arms, railway lines with their locomotives and rolling stock, military resources - all were diverted away from the battlefields and squandered on the Holocaust. The Germans were willing to condemn themselves to military defeat, to destruction, just in order to murder a few more Jews.
And today, when we have come home and are once again living free in our own homeland, we still witness how our enemies around us are willing to condemn themselves to squalor, to miserable and meaningless existences - just in order to show the world how nasty the Jews are behaving to them.
The prophet Jeremiah expressed this powerfully in one of his magnificent messianic prophecies:
"All your devourers shall themselves be devoured, and all your oppressors shall all of them go into captivity, and those who trample you shall themselves be trampled, and all those who despoiled you, I will give over to be despoiled. For I will bring up a cure for you, and from your hurt I will heal you, says HaShem.... Thus says HaShem: Behold, I am returning the captivity of the tents of Jacob, and I will have mercy upon its abodes; the City will be built upon its hill-top, and the Palace will sit upon its designated place." (Jeremiah 30:16-18)
This prophecy has long since been infused into our national consciousness by being paraphrased in Lekha Dodi, 
This prophecy has long since been infused into our national consciousness.
the beautiful hymn that introduces every Shabbat: ve-hayu li'm'shisa kol shosayyikh, ve-nivnetah ir al til-ah - "and those who trample you shall themselves be trampled, and the City shall be built upon its hill-top."
All those who oppress us are ultimately punished measure-for-measure. Pharaoh's first decree was to murder the baby boys by throwing them into the River Nile to prevent the Jews from being redeemed; and the first plague, the beginning of the redemption, was the curse brought on the River Nile, and the redemption ended with the Egyptians drowning en masse in the Red Sea.
Such has been, and such will yet be, the fate of all those who dare oppress the Nation of God. All those who trample us are eventually themselves trampled. And the greatest and most delicious irony is that, so often, they bring their own calamities upon themselves - by the very means with which they sought to destroy us.