I’ll preface this by stating that I am not a maritime (or any other form of) law expert, nor do I play one on TV, but the topic of a private entity’s, whether human or corporate, right to defend itself on land or sea interests me.
Shipping firms use floating armouries to deter pirates:
Private security firms are storing their guns aboard floating armouries in international waters so ships that want armed guards for East Africa’s pirate-infested waters can cut costs and escape laws limiting the import and export of weapons.
The Somali pirates have made this a hot topic, but for a while, armed merchant ships have been taboo. Much credence is given to international opinion on prohibiting arms on commercial vessels and depending heavily on whatever navy ship may be in the area to come to a sieged ship’s rescue.
Given how many merchant ships already flies under flags of convenience, I can see where those nations whose flags the ships are flying under would establish their own weapons sales facilities in their ports and make it easy for mariners to gun up. I’m not sure where Liberia, Panama, et al. would pull their stockpile from, but there would definitely be the chance for them to make a steady income, given the dangerous waters that commercial vessels often find themselves in.
But what do I know? I’m just a spectator in the realm of geopolitics.