Has anyone actually needed a gun at sea?

I am ex-military and a gun guy, by most anyone’s standards. When in the US, I’m rarely far from a gun.
But, when we sailed down to Grenada and back in 2018-2020, we did not carry one. There were only three incidents where we felt threatened at all. Two were in St. Lucia. We will not be going back to those bays, if we ever even go back to that country. We also didn’t spend much time in St. Vincent (proper), although we loved the Grenadines. We will probably avoid those two islands in the future, as well as any others with an increased threat level against travelers.
We do have two large dogs. So, that could very well add to our sense of security, and in fact our real security.
The third one was far out at sea, where a fishing boat came close. But, they veered off long before they got anywhere near boarding range, possibly after seeing our dogs and two alert crew members. They just continued on towards what was probably their fishing grounds. Frankly, that whole thing was probably just a coincidence with our paths crossing very close.
Many countries will confiscate your gun while you are in the country, and I suspect those tend to be the countries where you might actually want it. Those that don’t often have all kinds of hoops to jump through when you declare it. Of course, failure to declare it can make things very interesting if they ever find it, or you use it.
I suspect the better strategy is just to avoid areas that present an increased threat level against travelers.
It is difficult to keep track of the different laws in the different US states, as far as ‘stand your ground’, etc. I have no idea of those sorts of laws in Caribbean nations. But, I do know that local law enforcement is likely to take a very dim view of a foreigner shooting their cousin, for example… I’d rather avoid that whole situation.