What are the elements of an attempted murder?

The statutes at issue here prohibit the attempted killing of "a national of the United States," 18 U.S.C. 2332, and "any officer or employee of the United States while such officer or employee is engaged in or on the account of the performance of official duties," 18 U.S.C. 1114. Because the statutes do not specify the elements of "attempt to kill," the elements are those required for attempted murder at common law, which include an intent to kill. See Braxton v. United States, 500 U.S. 344, 351 n.* (1991).