“But there has always been one truly unifying force in human history. One call that would always unite you. The emergence of a common enemy. That enemy was the Covenant.
When this new foe emerged and declared war against humanity, you finally united under a single banner. And the weapons you so carefully constructed to control your own baser instincts were now aimed not at yourselves, but against a deadly opponent. In our pursuit of a shared goal. The very survival of your species.”