((a)) ** .—** There is jurisdiction, including extraterritorial jurisdiction, over an offense under this chapter if the prohibited activity takes place—

((1)) within the United States and within waters subject to the jurisdiction of the United States; or

((2)) outside United States and—

((A)) an offender or a victim is a national of the United States (as that term is defined under section 101(a)(22) of the Immigration and Nationality Act ();

((B)) the activity involves a vessel in which a national of the United States was on board; or

((C)) the activity involves a vessel of the United States (as that term is defined under section 2  of the Maritime Drug Law Enforcement Act (46 U.S.C. App. 1903).

((b)) ** .—** Nothing in this chapter shall apply to otherwise lawful activities carried out by or at the direction of the United States Government.