MARTHA CRAIG DAUGHTREY, Circuit Judge. Petitioner Gary Duane Harris appeals from the district court’s denial of his second or successive 28 U.S.C. § 2255 motion to vacate, set aside, or correct a portion of the 480-month sentence he presently is serving. After pleading guilty to aiding and abetting second-degree murder, aiding and abetting attempted robbery, and aiding and abetting using or carrying a firearm during and in relation to a crime of violence, the district court sentenced Harris to concurrent sentences of 420 months and 180 months for the second-degree-murder and attempted-robbery convictions, respectively. The district court also imposed a consecutive 60-month sentence for the firearm conviction.

Harris argues that the consecutive 60-month sentence must be vacated because it is possible that the district court imposed that punishment pursuant to the unconstitutionally vague “residual clause” of 18 U.S.C. § 924(c)(3)(B). Furthermore, Harris insists that the 60-month sentence cannot be saved under the so-called “elements clause” of 18 U.S.C. § 924(c)(3)(A) because neither his conviction for aiding and abetting second-degree murder nor his conviction for aiding and abetting attempted robbery could have been considered a “crime of violence” under caselaw existing at the time of sentencing.

Although it is possible that Harris could demonstrate that his sentence is constitutionally suspect, our inquiry does not end there. To justify relief under § 2255, Harris must identify not only constitutional error but also harm that he suffered from that error. At best, Harris can show that the record of his sentencing is silent as to whether the district court relied upon § 924(c)(3)’s elements clause or residual clause when imposing punishment upon him. Thus, even if the record’s utter silence is sufficient to show that Harris’s sentence is constitutionally suspect, Harris still must establish that he could not have been sentenced to the consecutive 60-month prison term under § 924(c)(3)’s elements clause. Because the 18 U.S.C. § 2111 crime of aiding and abetting attempted robbery necessarily constitutes a crime of violence under the elements clause of 18 U.S.C. § 924(c)(3)(A), we affirm the judgment of the district court.