Yesterday Pirates of the Burning Sea was officially released, and port contention PvP was enabled. Which lead to a lot of ... PvE. Because curiously port contention PvP contains very little actual PvP, but instead has hours of PvE grind. To put a port into contention you need to attack NPC merchants of the defending nation close to the port you want to take over. So if for example the Spanish want to take the British port of Belize (which is probably happening right now on every single server in PotBS), they have to sink British NPC merchants in front of Belize. Now you would think that to defend Belize, the British would need to sink the attacking Spanish players. But no! To defend Belize the British would need to sink Spanish NPC merchants in front of Belize, of which there aren't many, because the current nationality of a port determines what NPC merchants are around. The British could also run special defensive PvE missions, or hand in crafted goods to defend the harbor. But gaining contention points for the attacker is fast, and there is nothing to gain from defending, so nobody bothers. Especially not with Belize, which is far from the British starting area.
Why do the Spanish attack Belize? Because it has a strategically important resource, fir, and is conveniently close to the Spanish starting area. So is this economic warfare, the Spanish depriving the British of fir? No, Pirates of the Burning Sea doesn't work like that. When Belize becomes Spanish, the British fir log camps there pay a higher tax on production, and so the British players might be tempted to leave. But in all likelyhood Spanish players will build fir logging camps at their place. And for the players just wanting to buy fir, nothing changes. A freetrader can buy fir in the auction house of any nation, and there is no penalty or higher cost involved in buying from the enemy. The Spanish don't sell fir for more than the British did, so for the buyer nothing changes.
As a freetrader I actually prefer Belize switching to Spanish and staying there, in contrast to the British trying to take it back. Because only if the port is in contention do I risk to be attacked by player pirates and privateers when transporting goods to and from that port. If the port is firmly in enemy hands, it is totally safe for me to go there and buy my fir.
24 hours after the Spanish reach a certain contention level in Belize, there will be a port battle of 24 Spanish against 24 British players. In theory the British could defend Belize at that point. In praxis Belize is still far away from the British starting area, there is still nothing to gain from defending the port, and there won't be enough British turning up to defend the port. The Spanish will continue to attack British ports on the left side of the map, the British will attack Spanish and French ports on the right side of the map, and rarely do the nations ever meet. Now my judgement might be clouded by me not liking PvP in general. But I'd say that the PvP system in Pirates of the Burning Sea is particularly stupid.