Does a zippered suitcase have to be locked when traveling abroad?

Do you want the items in your suitcase to be valuable? You can't put valuables in it, just take it with you. If there are no valuables or information in the box, it doesn't matter if it's not locked. When we went to the United States, the rules were that we couldn't lock it. If anyone locked it, the customs officers would If you check it, your lock will be knocked off. You are responsible for it. This is indeed the case. For the sake of safety, we specially used a plastic tie on the handle of the trolley suitcase, and waited until I picked it up. When I was unpacking the box, I found that the ladder had been cut off. . .