The plant pest law—which is cited as the reason why ants cannot be transported across state lines, and especially from other countries into the United States—defines a plant pest as any non-human organism which causes or can potentially cause direct or indirect damage or disease to any plant or plant product.
This law does not differentiate between animals that can reproduce and those that cannot, and "ants" are mentioned nowhere specifically in the law. Therefore, it is really frustrating to continue seeing longstanding members of this forum make those differentiations which do not exist, at least with respect to the law.
With regards to sterile ant workers, even Pogonomyrmex workers sold in ant farms required a waiver by the USDA at one point. If one were advertising and shipping worker ants to customers all over the US, one would likely pop up on the USDA radar and be asked to apply for an exemption, as well. I repeat: the law does not differentiate between organisms that can reproduce and ones that can't.
Edited by drtrmiller, January 5 2018 - 6:36 AM.