I'm surprised, but that's fine, don't worry. More often, my challenge is to ask a question that I could get an answer to within a minute.
What I understand from your comments is that checks are done at the borders, but you're not able to tell us how they are done.
I do know, however, that there are all kinds of ways to send things in the mail. As an individual, I sometimes order things and find that the message written on the envelope to me, as an importer, is different from the message written by the exporter. There are all kinds of ways of going about it. For example, some shipped items are declared as gifts, which puts them in a different shipment category.
Do you think there are a lot of goods that are slipping through the cracks and could pose a real danger to our security from the People's Liberation Army?