Methodical Genocide? First Herod issued a decree that all children under two were to be killed, calculating the birth year of the two-year-olds in question from the description of a star seen from the east by the three wise men, whom he met. He was trying to solve the problem of the Messiah having been born and the next genealogical king of Israel having been born by murdering everyone counted in the census as having been born the same year as Christ. Herod was apostate enough that he likely only cared about his ownership of the scepter and throne, but that's not really the point. The point is that he tried to murder a generation of children, all those Hebrews born in a certain year, which is the origin of the word genocide, meaning to methodically annihilate a generation.
This has a mathematical meaning in terms of the racial census. A generation isn't a span of time, it's not the 18-20 years of so that it takes a year's crop of babies to grow up enough to have babies of their own, it's the total number of children born in a certain race in a certain Calander year. Herod was lower than Pharoh, as defined in the writings of Solomon, as he ordered all of his own race born a certain year wiped out, both boys and girls. Pharoh was only guilty of alienation and enslavement, and his country was given an across-the-board chance to save its children by painting the Passover sign of the doorposts and the lentil.
That was the first year of his life, Jesus was counted by an occupying power but ordered killed by the local governor, who had access to the foreign census record. This caused His family to have to sojourn as aliens in Egypt, historically an enemy of Israel and Greece, also historically an unfriend of Rome. Herod thought that he would prevent Jesus from either establishing a family or ascending the throne, which was part of the reason that He stayed completely out of state affairs and concentrated all of his efforts entirely on the ministry. There is no evidence that Herod ever rescinded the order or that not all of the babies born that year were not executed, unless maybe they could pay bribes or prove that they were loyal to Herod. The court of the Sanhedrin was corrupt, after all.