Welcome to America. Quite a few of our US captains ride with pistols, revolvers or even in one case an A-15 assault rifle on his back on occasion. Some States allow open carry as stated earlier and others even allow concealed carry. Quite common as many brands and varieties of biker leather vests come with concealed holsters. I unknowingly received one of those type of leather vests in Australia.
I live in anti gun Massachusetts and I carry when I ride. Vermont, New Hampshire and Maine are constitutional carry states so no worries crossing the boarder to the north for me. South is another ballgame.
A pistol is a legal tool that’s can be carried according to various state laws. I carry as is lawful as is my right and hope it is never needed just like my can of tire inflator.