I appreciate all the supportive statements. My Bladeforums experiences are typically pleasant and professional. I would like to provide a quick and painless lowdown on Guam. Customs to Guam is an agricultural drill. The island has an encapsulated eco-system so there's paranoia regarding new bugs. Although knife laws are relatively liberal, there are few hobbyists on the island. Regarding USPS, most residents pick their mail up at one of the USPS locations. Home delivery is limited. Planned Unit Developments (tracts) have been around for 35 years and are growing but many of the local Chamorros live in multi-generation, family compounds and strongly identify with the village in which they live. Limited residential street signage precludes home delivery to much of the island. Going to USPS to retrieve actually simplifies the delivery and receipt process. USPS tracking updates aren't always timely, but eventually packages track right up to USPS Guam Mail Facility in Barrigada - where I pick up my stuff. So, absolving worried senders is low risk on my part. USPS Priority East Coast to Guam is 10 or so days. A few days less from the west coast. USPS mail destined for the Western Pacific is sorted in Hawaii. Adds a few days. USPS shipping costs are exactly the same as mailing from and to any location in the U.S. The water is 86 degrees and you can see a hundred or more feet down. Just sayin.
I can attest to the customs drill. I entered the island twice with 3 double edged diving knives, one being a dagger, and a folding victorinox gardener. The only knife related question I was asked was if any of my knives were spring loaded, aka, switchblades. The rest of the questions were about bringing in shells, plants, or other flora and fauna from off of the island. And I can attest to the fact that the water is 86 degrees and you can see a hundred or more feet down.
There should be no problem shipping knives to Guam or any other incorporated, unincorporated or trust territory of the US.