- last post: 01.01.0001 12:00 AM PDT
Sorry to have to point this out, and please correct me if I am equally confused but I believe you've juxtaposed a few elements of the halo plot.
Firstly, cortana near the end of halo 2 was to blow the reactors of in amber clad if the ring was to activate, since the arbiter didn't allow this to happen cortana had no need.
Secondly, she would only have been able to destroy High Charity if she had destroyed delta halo, meaning the death of miranda keyes, johnson and numerous other friendlies, and presumably herself. Cortana was merely left in High Charity as a precaution, in case the ring did activate, and did not have control over High Charity (at least not enough to destroy it).
Please clarify if I am mistaken.