OKAY SO I WANT EVERYONE TO BE CLEAR HERE ON THE ARBITER (Thel Vadam). HE WAS THE SUPREME COMMANDER OF THE FLEET OF PARTICULAR JUSTICE, OR THE COVENANT YOU FACED ON ALPHA HALO IN COMBAT EVOLVED THAT HAD FOLLOWED YOU ALL THE WAY TO THRESHOLD FROM REACH.
So basically, he was leading that fleet, and in Halo 2 the Prophets accused him of allowing 1) for the humans to land on the ring and b) for the ring to be destroyed, when in reality what happened was there was a minor prophet in his fleet that was trying to usurp his position and take control of the mission.
To the prophet, the involvement of such an important holy relic such as a sacred forerunner ring had just turned this operation into a religious matter.
So no, Thel was not dumbstruck by the ring, he was trying to manage an entire fleet, do battle and stave off humans on the ring, deal with other problems arising such as the parasite on the surface of the ring threatening to board his ships and overtake his fleet, one of his high-ranking officers (Rtas Vadumee) returning alone from what was supposed to be a by the book check in on an agricultural ship that had seemingly gone dark, mangled after a run in with the Flood left him dismembered and teamless, all the while trying to keep his hands on the reigns so the prophet didn't derail his whole operation.
It's okay though, because the decisions that prophet made led to the Heretic Uprising, and eventually the Great Schism. I just want y'all to realize Thel was a brilliant tactician and a glorious fighter. He wasn't what the prophets made him out to be, made the Covenant believe he was, made him believe he was.
Even Guilty Spark told Sesa Refumee (the Heretic Leader) that the Prophets have always been lying and manipulative.
