Discussions about hardware often circle around specifications, tainted by aesthetic preferences and patriotism. Several psychological aspects are often missed - it doesn't need to be like that.
One psychological effect isn't about mind tricks like fear or panic, but about restricting behaviour. It's about - who could not have guessed that after reading the title? - repulsion. There's a quite robust chance that even those who've read a hundred books on military theory don't have come across that term or that idea yet. I encountered it ("abstoßend") in some post-WW2 sources which were written under the impression of the intense world war fighting.
These sources diagnosed the phenomenon and didn't analyse it at all.
The idea isn't even outlandish; some weapons have a great value because they keep the enemy at a distance - with a chance of discouraging attacks and scouting attempts completely within their effective range. That's the (highly valuable) influence on enemy behaviour; the range of promising enemy options (opportunities) is being reduced.
War is much more about taking many of the enemy's options off the table than it is about killing and destruction.
One example: The Allies didn't start Operation Overlord or an equivalent in 1943 because German defences were repelling enough to sweep that option off the table.
A common remark about warfare is that it's 99% boring. Yes, the repelling power of enemy capabilities is among the reasons for this.
It's a good thing to consider repulsion because it has an independent effect on the utility of hardware.
An example scenario should show this; a unit has two possible approaches for enemy attacks in its defensive sector, 2 km apart.
In the first case it's equipped with a weapon of 1.5 km range and able to cover both approaches. A specifications-based analysis shows that the unit can be happy about the range. More range = better. The enemy sees the same and concludes that he's got the choice where to execute an ordered attack, because he'll get shot at anyway.
Now the second case; the unit gets a fixed weapon with only 500 m range. It cannot cover both approaches at once and needs to settle with the defence of one approach, leaving the other one undefended. The specs-based analysis explains why the unit's leaders are unhappy, the enemy sees the gap and exploits it.
There was no repulsing effect against a determined enemy in the first case, but in the second (superficially terrible) case there was a repulsing effect; the attacker was likely kept from attacking the defended approach.
A simple tactical analysis would certainly judge the first case to be much better one for the defender, and the second case a free win for the attacker.
Well, I beg to differ.
There was no way how the "case one" unit could serve its superior HQ in any other way than with some mere attrition (and delay) of the attacker.
The "case two" unit shaped the battlefield by making the attack's route predictable. In fact, the attacker's route could almost be dictated in the second case.
That's a very valuable service for the superior HQ and it could by far outweigh the company's full firepower.
Maybe it doesn't outweigh the loss of attrition by the line units; even in that case an analysis that doesn't take repulsion into account would fall short of depicting the situation accurately.
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WW2 veterans made remarks about the repulsing power of modern infantry arms in general and also in regard to the then-new short-range anti-tank weapons. I have never ever seen similar remarks in regard to air power or artillery.
The point here is that although more range is often considered to be an advantage, it doesn't need to be one. A greater effective range can easily cause a loss of the tactically and operationally often more valuable repelling effect.
This should be taken into consideration because the effect may be very great on the levels of brigade to division command. A bunch of 2 km-ranged weapons may be able to discourage an attack (short of a major breakthrough offensive) at a particular place while a 80 km ranged weapon at 40 km distance may be unable to do the same. It would cover all relevant locations with almost the same firepower and would thus fail to repel offensive intents anywhere.
Its effect would appear on both sides of the attacker's options inequation and would thus cancel itself out in the attacker's consideration of the relative virtues of alternative routes.
Granted, repulsion is the tactical relative of deterrence. Yet, it's very different at the same time; deterrence is meant to prevent offensive action completely, while repulsion is a local effect that merely keeps the inevitable away from certain locations.
Repulsion is one of the most influential factors in ground, air and sea warfare, yet it doesn't seem to have gotten its proper place in military theory yet.