Sci-fi stories often feature ray guns but rarely consider the nature of energy sidearms:
The main advantages of laser weapons include: weapon bolt travels at the speed of light, excellent accuracy, damage inflicted by the bolt can be dialed up or down, lasers have no recoil, and the “ammunition” (i.e., electricity required per bolt) is much more inexpensive than the equivalent conventional bullet.
The main disadvantages of laser weapons include: it still requires huge amounts of power, bullet ammo takes up far less space than power generators, it has far more of a waste heat problem than a conventional firearm, and the energy in a given bolt is severely reduced by dust, smoke, clouds, or rain.
Pretty much zero science fiction stories, movies, or TV shows mention that laser sidearms have the ability to permanently blind anybody closer to the weapon than the horizon. If the beam is in the frequencies that can penetrate the cornea of the eye, and the beam reflects off a door nob or other mirrored surface, anybody whose eyes get flashed by the beam is going to need a seeing-eye dog. There are more hideous details here.
Laser pistols don’t make sense though until you have a portable power source.
I got a kick out of this excerpt from Robert Heinlein’s 1942 story Beyond This Horizon, where Monroe-Alpha notices that Hamilton is “armed with something novel… and deucedly odd and uncouth”:
“What is it?” he asked.
“Ah!” Hamilton drew the sidearm clear and handed it to his host. “Woops! Wait a moment. You don’t know how to handle it — you’ll blow your head off. ” He pressed a stud on the side of the grip, and let a long flat container slide out into his palm. “There — I’ve pulled its teeth. Ever see anything like it?”
Monroe-Alpha examined the machine. “Why, yes, I believe so. It’s a museum piece, isn’t it? An explosive-type hand weapon?”
“Right and wrong. It’s mill new, but it’s a facsimile of one in the Smithsonian Institution collection. It’s called a point forty-five Colt automatic pistol.”
“Point forty-five what?”
“Inches… let me see, what is that in centimeters?”
“Huh? Let’s see — three inches make a yard and a yard is about one meter. No, that can’t be right. Never mind, it means the size of the slug it throws. Here… look at one.” He slid one free of the clip. “Damn near as big as my thumb, isn’t it?”
“Explodes on impact, I suppose.”
“No. It just drills its way in.”
“That doesn’t sound very efficient.”
“Brother, you’d be amazed. It’ll blast a hole in a man big enough to throw a dog through.”
Monroe-Alpha handed it back. “And in the meantime your opponent has ended your troubles with a beam that acts a thousand times as fast. Chemical processes are slow, Felix.”
“Not that slow. The real loss of time is in the operator. Half the gunfighters running around loose chop into their target with the beam already hot. They haven’t the skill to make a fast sight. You can stop ‘em with this, if you’ve a fast wrist.
Shooters make the same point about laser sights today.