Unarmed V-bombers were not guarded.
You've obviously never encountered a proud Crew Chief.
Not guarded? There were usually one dog and his man to a pair of dispersals. The dog handlers provided us with much amusement during idle moments waiting in the crew hut for an inbound; when he's at Delta 13, make a call to Delta 14 and watch him walk to the phone, then hang up and call Delta 15 ad infinitum. It often took three circuits of the dispersal before they gave up. On another occasion, the dog attacked the handler on Bravo. With the dog mauling his leg, the Plod managed to unpack his bullets from the green, greased paper packets, load them into his magazine, cock his pistol and shoot it, much to the merriment of one Starter Crew on Charlie dispersal.
So, yes, there were guards around the aircraft and yes, they were armed and dangerous - but not necessarily to intruders.
