What does Exodus 1:9 mean?

Pharaoh describes a growing problem to his Egyptian people. This problem involves two specific areas. First, he notes Israeli numbers had grown from seventy (Exodus 1:1–7) to somewhere possibly in the millions or nearly two million. Later verses indicate that Israel would continue to grow, despite oppression (Exodus 1:12). Second, Egypt's king worries the Israelites are "too mighty for us." Based on numbers alone, he is also concerned the Israelites could form an army and defeat the Egyptians in a time of war. Or, they could be convinced to join the enemies of the Egyptians to defeat them in an invasion (Exodus 1:10).

The first resolution attempted by Egypt's king is forced labor (Exodus 1:11). The enslaved Israelites are noted for building two cities, Pithom and Raamses (Exodus 1:11). Both cities were south of the capital of Zoan along tributaries of the Nile River leading to the mouth of the Mediterranean Sea. They were known as store cities. Though the exact meaning of "store cities" is uncertain, it is clear these cities were some kind of supply areas used by the Egyptians. They may have served as a continuation of Joseph's food storage efforts from the seven years of plenty when all Egyptians began the tradition of storing part of their grain.