which the Commission may specify a sentence at or near the maximum.” United States v. Baker, 16 F.3d 854, 857 (8th Cir.1994). But, § 994(h) “merely declares that the enumerated crimes must be so treated.” Id. Application Note 1 does not provide an exhaustive list of “controlled substance offenses.” The Commission addressed § 841(c)(1) in response to a circuit conflict about whether possession of a listed chemical with intent to manufacture a controlled substance is a “controlled substance offense.” United States Sentencing Commission, Guidelines Manual, app. C., amend. 568 (2003) (eff. Nov. 1, 1997). The Commission did not address § 841(c)(2) in Application Note 1 because it was not at issue in the circuit cases. Compare United States v. Calverley, 11 F.3d 505, 511-12 (5th Cir.1993) (<HOLDING>), aff'd en banc, 37 F.3d 160, 165 (5th
holding that mens rea required for possession of a controlled substance is knowledge that defendant possessed a controlled substance holding that possession of listed chemical with intent to manufacture controlled substance is controlled substance offense holding that because some form of intent to manufacture import export distribute or dispense is not involved simple possession of a controlled substance does not constitute  a controlled substance offense for purposes of united states sentencing commission guidelines manual  4blla holding that quantity of the controlled substance does not have to be measurable to support a conviction for possession of such controlled substance particularly when the immeasurable amount of the substance is found on an implement used to consume the substance holding that possession of a controlled substance is a crime only if the defendant knowingly possesses the substance and has knowledge of the nature of that substance