Okay kiddo, so Customs Trade Partnership Against Terrorism (CTPAT) is a program that helps prevent bad people from doing bad things using cargo containers.
You know how we get so many things from different countries? Well, those things come in big boxes called cargo containers. And sometimes, bad people might hide bad things in those boxes, like weapons or drugs.
But with CTPAT, companies who ship those boxes join the program and work with the government to make sure the boxes are safe. They do things like make sure the boxes are locked and sealed properly, and that they only do business with other companies that follow the same safety rules.
This way, we can make sure that the things we get from other countries are safe, and that bad people can't use them to hurt other people. Isn't that cool?