Securing Americans from Transportation Insanity Act This bill prohibits the Transportation Security Administration (TSA) from modifying Standard Operating Procedures to remove biologically determined sex-based screening procedures from security screening, including by (1) updating the TSA PreCheck program to include an 'X' gender marker option, (2) promoting the use and acceptance of the 'X' gender marker, and (3) requiring U.S. Customs and Border Protection to use gender-neutral language and an individual's self-identified pronouns or name.