What is the test for ineffective assistance of counsel in a federal habeas?

The two-step inquiry from Strickland v. Washington governs a federal habeas petitioner's claim of ineffective assistance of counsel. 466 U.S. 668, 687 (1984). First, a criminal defendant must show some deficiency in performance by counsel that is "so serious that counsel was not functioning as the counsel guaranteed the defendant by the Sixth Amendment." Id. This court must ask whether the attorney's strategic choices were reasonable under "prevailing professional norms" and "indulge a strong presumption that counsel's conduct falls within the wide range of reasonable professional assistance." Id. at 688-89. The entire performance of the attorney must be considered; it is "difficult to establish ineffective assistance when counsel's overall performance indicates active and capable advocacy." See Richter, 562 U.S. at 111 (2011). Second, the defendant must show that the deficient performance caused him prejudice. See Strickland, 466 U.S at 687. This requires petitioner to show "that there is a reasonable probability that, but for counsel's unprofessional errors, the result of the proceeding would have been different." Id. at 694.