; (2) research and develop a mechanism to share aggregated Federal information regarding United States-sourced firearms, including ghost guns, recovered in Mexico in support of carrying out subsection (a); and (3) develop performance measures to assess the effectiveness of U.S. Immigration and Customs Enforcement activities aimed at combatting homeland security threats, including border security threats, and illicit cross-border activities involving United States-sourced firearms, including ghost guns. (f) Definitions In this section: (1) Act of terrorism The term act of terrorism has the meaning given such term in section 3077 of title 18, United States Code. (2) Fire control component The term fire control component means a component necessary for a firearm to initiate or complete the firing sequence, including a hammer, bolt or breechblock, cylinder, trigger mechanism, firing pin, striker, and slide rails. (3) Foreign terrorist organization The term foreign terrorist organization means an organization designated as a foreign terrorist organization under section 219 of the Immigration and Nationality Act ( 8 U.S.C. 1189 ). (4) Ghost gun The term ghost gun — (A) means a firearm, including a frame or receiver, that is privately made or which lacks a unique serial number engraved or cast by a licensed gunsmith, manufacturer, or importer, or was removed, obliterated, or altered in accordance with chapter 44 of title 18, United States Code; and (B) does not include— (i) a firearm that has been rendered permanently inoperable; (ii) a firearm identified by means of a unique serial number assigned by a State agency and engraved or cast on the firearm before the effective date of this Act in accordance with a State law; (iii) a firearm manufactured or imported before December 16, 1968, or unless the Attorney General has provided otherwise by regulation with respect to the specific make and model of firearm on or before January 1, 2024