Girls on the Left; Boys in the River

Exodus 1:16
...if it be a son... When a woman marries, ideally she leaves her father's people and joins her husband's. Hebrew women were as accustomed to this institution as were their contemporaries. Pharaoh knew that their daughters would be much easier than their sons to assimilate into Egyptian society. If his goal was only population control, one might think Pharaoh would have been wiser to kill the girls, thereby reducing the number of Hebrews for two generations instead of only one.  However, there were three good reasons to target boys.

1. If he had been successful, then the next generation of Israelites would have been Egyptians. He would have eliminated the Hebrews forever, while dramatically increasing the number of Egyptians in the next.
2. Battles are fought by men. By God’s design, they are more likely to forcefully resist oppression.
3. As a shadow of Yeshua, Moses’ arrival was almost certainly prophesied. Pharaoh, like Herod centuries later, thought to circumvent God’s design through force.

Update January 20, 2009: This could almost make one become a conspiracist: Declining Male Fertility Linked to Water Pollution.