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Back in World War Two,
fighter-bombers,
light bombers,
Stukas and
more or
less armoured Shturmoviks attacked the difficult ground targets;
supply transports on the ground (rail, trucks, horse carts)
, troops on the march and
deployed troops.
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These small targets were impossible to detect and identify from high altitude, were difficult to hit, moving (= position not known when the aircraft took off) and at least troops on the march were even dispersing and firing back in reaction to attacks.
The munitions used were machine gun bullets, bombs of different kinds and especially late in the war cluster bombs and unguided rockets.
It was possible to use
spiked bombs to leave a bomb as a mine at a railway track, and railway traffic was generally quite easily disturbed because of the indefensible, exposed static rails. Trucks weren't ubiquitous back then, so railway traffic was most important in the rear areas. Most ground attack aircraft on the Eastern Front didn't penetrate deeper than 10 or 50 km, though. It was usually more efficient (fuel, pilots) and less risky to fly two short incursions than one deep one.
The one thing that did not change much from 1944 to 2012 is the continent. Landscapes changed (especially by urbanisation), but railway networks are still similar and the size of the territories did not change (except the coastlines).
Modern army logistics changed more; logistics are much more about heavy trucks than in '44; railway connection got busted? No problem, just use more trucks. Many armies rely almost entirely on truck logistics anyway. We can do this easily, thanks to millions of heavy trucks in Europe. Back in 1944
a few thousands of much less capable trucks was a major effort.
So nowadays we couldn't cut off supply traffic (do interdiction) so well because
a) the vulnerable railways can easily be substituted
b) there's a practically endless supply of capable trucks
c) modern 24/7 attack sensors make the night no less dangerous than the day, so the enemy is not provoked to constrict his supply runs to the night. They just keep moving forward, damn the torpedoes bombs.
Supply interdiction would likely only have a very short-term effect, by producing supply delays. A rare exception would be a main supply route on land into Lithuania because of an extreme shortage of roads and anything resembling roads.
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What about troops on the march?
Today's ground troops are at least motorized, if not mechanised. A brigade column may be many kilometres long, but it would have spacing between vehicles (50-100 m, it depends) and the column would usually reach its destination within a few hours.
How many attack planes would engage this column in two or three hours? Certainly only a fraction of those which are in the air during that period, for most will be on combat air patrol, suppression of enemy air defence, reconnaissance or structure attack mission (with poorly suited munitions) or be forced to abort due to aerial opposition.
Back in WW2, all pilots had the choice whether to strafe a column or not, for their machine guns were adequate weapons. Today's combat aircraft have 20-30 mm autocannons, but only the A-10 has a really meaningful amount of ammunition on board. The others could not strafe much better than an average WW2 fighter; clearly unsatisfactory considering the inexhaustible supply of vehicles and the small quantity of modern combat aircraft.
What's more; back in WW2 troops on the march were rarely well-armed to fend off air attacks. Nowadays there's the ubiquitous ManPADS missile threat and there are still SPAAGs (anti-air vehicles), too. The old strafing attack is simply not worthwhile any more against capable opposition.
Well, maybe you remember
the photos of burned-out wrecks from Iraq's withdrawal from Kuwait in 1991.
* no modern ManPADS
* no effective SPAAGs
* no concealment
* only one major route available
* long-lasting troops movement
* poor march discipline (spacing)
* extremely lopsided conflict in general (training, equipment)
As so much else that happened on Arabian terrain, it's simply not representative for what would happen in higher developed warfare on more cluttered terrain. Consider those photos as as representative for modern air interdiction as was the
Great Marianas Turkey Shoot for modern air war.
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Last category; troops in the field (
close air support).
Clearly, air power has huge challenges in CAS because of fratricide and generally chaos problems. It helps a bit that ground observers help air power, but the more close air power is bound to ground observers, the more it becomes a substitute for artillery. 100 million € aircraft are a really, really expensive substitute for artillery. That is part of the reason why there won't be enough CAS missions to satisfy high expectations.
Air force leaders are not inclined to allocate much air power to CAS in a conventional campaign because it's rather inefficient and there are too many fixed demands (combat air patrols et cetera). The exception are emergency concentrations of combat aircraft on CAS missions on the spot of a local crisis (=battle not yet won; see
Battle of Khafji).
Why did I write this?
I've encountered more than once the idea that air power has become so powerful, so accurate, so all-seeing today that it could, no, WOULD wipe out entire brigades at ease and cut off supply as well.
This belief was already present in "Air-Land Battle" doctrines, which were "very optimistic" about air power.
I don't trust this idea at all. The now effective defence against simple low-level attacks, the huge supply of motor vehicles, the complexity of the clustered European terrain in comparison to Arabian (half) deserts, the moderate quantity of combat aircraft and the rather specialised munitions even of multi-role combat aircraft oppose the idea of the all-powerful tactical air.
True, a brigade could be wiped out from the air IF a hundred Typhoons laden with almost only Brimstone missiles attack it. The problem is that a Polish infantry division was practically knocked out at a railway station by a Stuka wing in September 1939 as well, a feat that rarely had equals later on. Perfect storm events such as this are rare and should not dominate our appraisal of tactical air power's utility.
S O
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