What is the test for a state court to reject a prisoner's claim of ineffective assistance of counsel?

A state court decision will certainly be contrary to our clearly established precedent if the state court applies a rule that contradicts the governing law set forth in our cases. Take, for example, our decision in Strickland v. Washington. If a state court were to reject a prisoner's claim of ineffective assistance of counsel on the grounds that the prisoner had not established by a preponderance of the evidence that the result of his criminal proceeding would have been different, that decision would be [contrary to] our clearly established precedent because we held in Strickland that the prisoner need only demonstrate a reasonable probability that ... the result of the proceeding would have been different.