While I enjoyed
Lurconis' somewhat humorous point about media-science fiction, I think perhaps the writers above need to read some
hard science fiction. The reason
beam weapons are so slow and visible on TV, is
so the viewers can see them working! Dramatic conventions are not necessarily a sign of incompetence. Moreover, our lives are not so different from many science fiction worlds. Many modern weapons, and ordinary
consumer goods employ some serious
technology.
An actual laser beam travels at the speed of light. You don't see it racing out from the 'blaster' like you can large cannon shells. If Flash Gordon were to use a real laser gun, all you'd see is his target exploding, which the audience would have a hard time attributing to Flash or his ray gun. A standard slug gun is seen as too passe by many viewers, who assume that in the future everything will be different. Yet guns are common in written SF because they work. Realistic weapons are common in written SF. For example, needle guns that chip material off a larger block of ammunition, are common because they can be lethal and hold many, many shots. Fusion bombs, x-ray lasers, and hurled asteroids are other practical SF weapons. A good example would come from Larry Niven and Jerry Pournelle's novel Footfall, which uses entirely realistic tech. Gene Wolfe's fantasy The Book of the Long Sun is full of needlers and slug guns.
Moreover, 'science fiction' technology is widespread within the real military. Today US soldiers can see in the dark, through fogs, and use laser beams as a matter of routine. Robots are everywhere. The US Navy has experimented with dolphins as mine hunters. They experimented with beam weapons back the 1950's. My father remembers seeing a demonstration beam weapon when he was ROTC. It was the size of a semi-tractor and could kill a rabbit at fifty yards. Not very practical, for the same reason that higher-powered beam weapons aren't found today. The power supplies are too bulky and costly. Star Wars brought us lasers, penetrators and high quality radars. Today's Army looks at forcefields to protect future tanks. Much of this stuff seems like pie in the sky, but last year's dream is tomorrow's product. Much of today's comforts began as the dreams of one engineer. Writers and engineers often pick each other's brains for ideas.
Most science fiction weapons are created to be futuristic, not realistic. Not every writer has the technical chops or interest to integrate the weapon precisely within his or her world. They're too busy telling a story. If you read someone who has taken his military work seriously, then you'll see some cool stuff.
It is possible to follow artillery shell visually in clear weather, and I knew one World War II veteran who saw the mortar shell that wounded him. But particle beams? Only in slo-mo .