What is the test for ineffective assistance of counsel?

To prevail on a claim of ineffective assistance of counsel, a petitioner must make two showings. First, he must demonstrate that his counsel's representation "fell below an objective standard of reasonableness." Strickland v. Washington, 466 U.S. 668, 688 (1984). Second, he must establish that he suffered prejudicein this context, meaning 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.