guilty of possessing a gun “in furtherance of’ his drug trafficking. Id. Since Watson, six courts of appeals have considered whether a defendant who receives a firearm in exchange for drugs possesses that firearm in furtherance of a drug trafficking crime, and all six have decided or assumed without deciding that such a defendant does violate § 924(c). See United States v. Mahan, 586 F.3d 1185, 1188 (9th Cir.2009) (“a defendant who accepts firearms in exchange for drugs possesses the firearms ‘in furtherance of a drug trafficking offense”); United States v. Sterling, 555 F.3d 452, 458 (5th Cir.2009) (assuming without deciding that bartering drugs for guns constitutes “possession in furtherance” of a drug trafficking offense); United States v. Dolliver, 228 Fed.Appx. 2, 3 (1st Cir.2007) (<HOLDING>); United States v. Luke-Sanchez, 483 F.3d 703,
holding that distinction between trading a gun for drugs and trading drugs for a gun is a distinction without a difference holding that acquisition of a firearm in exchange for drugs is a sufficient nexus to establish possession in furtherance of the drug sale holding that trading drugs for a firearm constituted use under  924c1a holding that trading drugs for a gun violates the in furtherance of prong of  924c holding that evidence is sufficient for  924c conviction where it shows weapons proximity to drugs and its accessibility