All of the US sailors I know are heavily armed. Aks, shotguns and pistols. They have multiple guns for all distances.
my guess is that you only know sailors in the US Navy or those civilians that sail on Government ships. Civilian sailors, Merchant Mariners, on civilian ships are not ALLOWED to have weapons on board US flagged vessels. I’ve sailed as a Merchant Mariner for 21 years. The only crews a that have weapons are those that sail on Government ships.
The best way to beat the pirates are to keep them off the ship. The ships’s speed and a high freeboard help the best.
The only way to stop this is to allow the Navy to blast them out of the water. Period. Destroy everything that floats and they will not have a way to get out to the shipping lanes.