to get more confusing...
§ 1241. Definitions
As used in this chapter –
(a) The term “interstate commerce” means commerce between any State, Territory, possession of the United States, or the District of Columbia, and any place outside thereof.
(b) The term “switchblade knife” means any knife having a blade which opens automatically –
(1) by hand pressure applied to a button or other device in the handle of the knife, or
(2) by operation of inertia, gravity, or both.
“Interstate commerce” means commerce (i.e. buying, selling and trading) between any of the 50 U.S. states, Washington, D.C., any of the U.S. Territories (e.g. Guam or American Samoa), and “any place outside thereof,” referring to all foreign countries. In other words, this means this term applies to selling, buying and trading between states, between a state and a territory, between a state or territory and a foreign country (i.e. importing). It does NOT refer to buying, selling or trading within a state or territory.