Way back when men wore leather boots and spurs, it was apparently common to have a long rifle and pistol in the same caliber if you could afford both- maybe a 9mm carbine and pistol combo would do the job.

Pistols are not useless, because unless you're always carrying your rifle at low ready you'll probably have it slung across your back or in your car- both worse than quick drawing your sidearm and dispatching the threat.