Joel Melo-Cedano appeals his conviction of illegal reentry in violation of 8 U.S.C. § 1326(a) and (b). He challenges the constitutionality of § 1326, claiming that “[o]r-ganic principles of American law (the law of nations) prohibits [sic] Congressional criminalization of America’s borders.” He maintains that “Criminalizing borders is anathema to the law of nations (an organic part of America’s common law).” He posits *348 that § 1326 is unconstitutional as applied to him because he was under the impression that he could apply for adjustment of status only from within the United States. The government has moved for summary affirmance in lieu of filing an appellate brief or, alternatively, for an extension of time to file its brief. Melo-Cedano has moved to file an untimely response to the motion for summary affirmance.

Because Melo-Cedano did not present the foregoing issues to the district court, our review is limited to plain error. See United States v. Howard, 766 F.3d 414, 419 (5th Cir. 2014), cert. denied, — U.S. —, 135 S.Ct. 1015, 190 L.Ed.2d 884 (2015). To establish plain error, Melo-Ce-dano must show a forfeited error that is clear or obvious and that affects his substantial rights. See Puckett v. United States, 556 U.S. 129, 135, 129 S.Ct. 1423, 173 L.Ed.2d 266 (2009). If he makes such a showing, this court has the discretion to correct the error, but only if it seriously affects the fairness, integrity, or public reputation of judicial proceedings. See id.

Melo-Cedano has not shown any clear or obvious error with respect to the constitutionality of § 1326. See United States v. Comstock, 560 U.S. 126, 135-36, 130 S.Ct. 1949, 176 L.Ed.2d 878 (2010); Puckett, 556 U.S. at 135, 129 S.Ct. 1423, In addition, “the crime of illegal reentry is not a specific intent crime, and a mistake of law is thus not a defense.” United States v. Flores-Martinez, 677 F.3d 699, 712 (5th Cir. 2012). Accordingly, Melo-Cedano’s as-applied, challenge to the constitutionality of § 1326 is insufficient to show error, plain or otherwise. See id.; Puckett, 556 U.S. at 135, 129 S.Ct. 1423.

The motion for summary affirmance is DENIED. See Groendyke Transp., Inc. v. Davis, 406 F.2d 1158, 1162 (5th Cir. 1969). The government’s alternative motion for an extension of time to file its brief is DENIED as unnecessary. Melo-Cedano’s motion to file an untimely response is GRANTED. The judgment is AFFIRMED.