I've noticed that science fiction movies have tended to turn away from depicting their future combatants with energy weapons, and towards equipment which looks as if it came out of the wars of the mid- to late-20th century. This is first noticable in Aliens, and has become increasingly prevealent since then.
This is one of the examples of the trend I've noticed in which, as we actuallly approach a technological development, there is a failure of nerve on the part of science fiction to anticipate it, while earlier science fiction had no such problem.
From H. G. Wells' "heat rays" to the "blasters" common in sf from the 1930's through 1970's, it was generally accepted for a long time that energy projecting weapons would replace matter projecting weapons in the long run. During the first few decades of this period, no actual means of projecting destructive energy existed. With the invention of the laser, it is interesting to note that sf, especially visual SF, tended to employ laser weapons.
We have now actually deployed destructive military lasers (Zeus and the ABL) and are very close to deploying several more. In the process, we have discovered the limitations of laser weaponry (atmospheric distortion, energy demand, recycle time). As with other technologies, this has created a failure of nerve on the part of sf authors, who (wrongly in my opinion) assume that the engineering obstacles which loom large at present will remain eternal barriers to the use of the technology.
And it looks pretty stupid, when you are talking about a star-travelling
society centuries in the future, to be using weapons whose design seems to have
frozen sometime between 1950 and 2000.
I offer this example of a hypothetical chivalric wonder story of the 15th century, by way of analogy:
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Rommel peered through his field glasses. The British had deployed on the rise, he saw. It would be a rough battle, but there was no way to go round.
"Attack!" he ordered.
Panzer III tanks rumbled forward. The metal monsters were equipped with stupendously huge lances, and even the plate armor of British knights could not stand before them. Their armor, in turn, was proof even against longbows. Such war wagons had broken the French pike phalanxes on the Meuse, and bid fair to win for the Reich at El Alamein now.
Suddenly the lead tank slewed out of formation, treads unravelling. The cry went up, the one every tanker dreaded ...
"Caltrops!"
The panzers were helpless, wallowing. And at that point the British reserves charged.
"For St. George and England!" cried Montgomery, standing atop the lead Sherman, whirling his mighty claymore ...
===
Silly, eh? No sillier than M-16's in the 25th century.