This is a copy of the response I received from the TSA about my complaint:
Thank you for your e-mail.
The Transportation Security Administration's current security screening procedures require all carry-on luggage and accessible property be screened before passengers take them onboard an aircraft. Regardless of whether an item is on the prohibited or permitted items list, the Transportation Security Officers (TSO's) have discretion to prohibit an individual from carrying an item through the screening checkpoint or onboard an aircraft if the item poses a security threat.
Therefore, TSA security screening personnel make the final decision on whether to permit items like a Tide pen into the sterile area of the airport. Should you need additional assistance, feel free to contact us at toll free 866-289-9673.
Please visit our website at www.tsa.gov (http://www.tsa.gov/) for additional information about TSA. We continue to add new information and encourage you to check the website frequently for updated information.
We hope this information is helpful.
TSA Contact Center