Although it will interesting if the missile shield ever becomes operational, in which case we might swing back to a defense-dominant system.

They have lasers now that shoot down certain types of rockets. How far will they go with these newer types of defences who can say? But as you stated above if they improve them enough the advantage of defenses will significantly increase.

Defense is... "possible"... but it's economic now. North Vietnam repelled the technologically-overpowering US because the US was dropping million-dollar bombs on dozen-dollar houses. The insurgents have held out in Afghanistan for so long for the same reason.

It's a shitty way to play "defense" though. I hate putting it in terms like that because it's attrition warfare of the worst kind, but that's what it is.

Counter-insurgency is different than 'normal' war, though. When you're fighting your own people, you're not going to carpet bomb them, or at least are going to restrain your offense. The USA was allied to the Republic of Vietnam but fighting an insurgency there. Ditto USA in Afghanistan.

Yeah, I follow ya. The examples were somewhat flawed -- my point's just that the only way to play "defense" in the nuclear era is by attrition. You can't actually stop a determined assault from some of the world's top military powers. Nukes, incredibly precise missiles, top-flight (heh) air forces, there's just no way to do it. You just have to hope to make the costs high enough that they don't bother attacking in the first place.

The way Putin set it up is the best way to theorize this. When you say "defense versus offense" we're not talking about petty little wars like in Vietnam of Afghanistan. We're talking WW2, or Korea or Desert Storm level wars. (Now when I say petty, I refer to the military might of each country - having major powers have a go at each other).

Throughout history you can see the back and forth of offensive versus defensive as new innovations come about. For much of Ancient Greece, defense was key, as Athens was able to hold out against a siege by Sparta for I forget how many years...a dozen? Then when Rome came into power, their innovations flipped the sides towards offensive. When castle building became wide-spread in the Middle ages it flipped again towards defensive. Then again with the introduction of gunpowder and again during....I believe it was Frederick the Great's time?

We are coming out of a period where offensive has been key. The second a missile defense shield becomes active, though, defense will be key.

Which is better for walking, your left leg or your right leg?

Defence vs Offence exists only in American Football. In the real world both concepts are so entwined that talking about them separately is meaningless.

But the relative ease of military conquest has varied over time. If you look at it from the point of view of the ratio of the cost of the forces the attacker requires to take territory to the cost of the forces the defender has deployed then it makes sense.

http://mitpress.mit.edu/books/offense-defense-and-war

The best form of defence is to run away...or the French think so anyway.

The two concepts are entwined because defense is all about making the enemy ground covered cost more than what they gain from expanding. Offense is all about gaining ground for a cheaper cost than what you paid to gain it. Simply by launching an offensive strike you are making it difficult for the opponent to launch their own, increasing your defensive powers in the area.

If we were to throw rationality of the combatants out the window and replace their pragmatic assets driven motives with the desire to destroy the enemy at all costs, defensive capability no longer has any real value for the combatant, and offensive capability obviously becomes more important.

I believe mankind has produced enough nuclear and biological weapons to eliminate itself from the surface of the planet. Under this aspect the offensive power is that great, that anyone of clear mind will not start a war anymore. So one could argue that offensive power is at the same time the best defensive instrument. And i believe a "missile shield" would not help anything. If one of the major countries wanted to ruin live at any cost - it could eradicate itself with its weapons. If you remember the worldwide Impacts of the tsernobyl reactor accident one can imgaine what a hundred / thousand / tenthousand or million time bigger impact such an action would have.

Why would a country want to eradicate itself? That has nothing to do with defence or offence. Also nuclear weapons are used by countries to detour wars. So in a strange way they are a defence.

As others have pointed out, defense vs. offense is largely a product of the technology of the time. The most stark example is WWI, where weapons technology greatly overpowered transportation technology. Why was trench warfare a thing? Because both sides had machine guns, artillery, and no way to circumvent the aforementioned machine guns and artillery. Remember, the Central Powers never surrendered. They just asked for peace first, because they were running out of shells and bullets faster than the Entente was running out of men to throw into the meat grinder.

Contrast that with WWII, when digging in did little to no good, largely due to advances in air power and armor, as Putin already mentioned. The Entente didn't have Sherman tanks, airborne divisions, and specialized ground attack aircraft in WWI, but they sure as hell did in WWII.

In a "low-intensity" conflict like Korea or Vietnam, you usually see a mix of offense and defense. Korea was one big running battle for over a year before the lines stabilized and it turned into a trench war. The trench war in Korea wasn't a product of too much power and not enough mobility; it was a problem of no political will on either side. Both China and the United States had more than enough resources to finish the fight one way or the other, but that was a risky idea from a political standpoint.

Same thing in Vietnam, although the type of fighting was dependent on terrain AND political capital. Khe Sanh and the other mountainous battles were largely trench battles for the Americans, whereas urban battles like Hue and patrolling in the jungle were running affairs. The United States had more than enough military power to completely conquer North Vietnam with conventional forces (which would have been a highly mobile campaign; there are few forces on Earth capable of stopping a sufficiently motivated column of M48 Patton main battle tanks), but no political will to do so.

Firepower > Mobility = Trench war
Mobility >= Firepower = Running war
Firepower = Mobility = War of attrition/mix of styles depending on other factors

... and my last post doesn't make any sense. Incorrect use of symbols. My apologies
*Mobility *>* Firepower = Running war

I actually think the problem with WWI was strategic ineptitude, not anything to do with technology. Military thinking hadn't caught up to the technology of the era. Sending waves of people after machine guns in the hope that you run them out of bullets before they bleed you out of lives is a strategy of mind-numbing incompetence, not a rational answer to strong enemy defenses.

Defense versus offense actually has a lot to do with the nations goals in the said war.

I think the main strategic error was the charges often lacked surprise (and German bunkers were very strong). Where there was surprise, they had some success. But for instance the main attacking waves at the Somme were preceded by hours of heavy bombardment. The Germans knew what was coming.

Anyway surprise is more a tactical issue, not strategic.

Heavy bombardment is actually quite ineffective against dug-in and disciplined troops. Being below ground level (even without ANY top cover) makes you 300% more likely to survive an artillery barrage. ("Brains and Bullets" by Leo Murray)

@ PE

Ineptitude was a huge factor, but the commanders had little choice besides frontal assault, at least at the beginning of the war. Frontal assaults were the only option until the introduction of infiltration tactics, sapping, and armor that was reliable enough to be an asset instead of a liability. Even then, the Entente breakthrough was a difficult and bloody one. Not defending anyone who advocated a massed infantry assault on machine guns, but not completely blaming them for the high body count either.

The French at the Somme actually attacked the German's southern flank with small groups and were fairly successful. Of course the Germans thought the French were exhausted from Verdun so weren't expecting it.

The commanders on both sides knew it was a war of attrition, and they persisted in the attack because the goal was to eliminate the reserves of an opponent they both believed to be on the brink of total exhaustion.

Defense versus offense has everything to do with technology, not political will. Its the ability to do something, not how things actually turned out. The fact that had the US wanted to invade North Vietnam they would have steamrolled through it shows that offense was dominant. The fact that the US could have bombed and invaded China into submission in the Korean war shows that offense was dominant - regardless of what actually happened or political reprecussions - shows that offense was dominant

I believe that the ongoing debate of which is better, offense or defense is best categorized by the economic principal of supply and demand. When there is a lot of powerful offensives minded weapons and strategies that leads to a high demand for strategies and weapons to combat them. So, that means strategists, innovators and engineers will put their efforts into supplying this demand for defense. Once this demand for defense has been met then the same will happen for offense and this cycle has been continuously ocurring and evolving ever since the first battles between opposing civilizations in ancient Mesopotamia.

@ goldfinger

I wasn't talking about defense versus offense. I was talking about trench warfare versus mobile warfare, which IS dependent on the political capital of the combatants. Korea would not have been a trench war for two years if Truman had lost his shit and decided to send the red Chinese communists back to hell.

I think the "defensive vs offensive" dichotomy based on weaponry, technology, tactics, is majorly flawed. Take two conflicts of the same era, WWII and the Korean war. One was decided in a series of offensive and counter-offensive campaigns that led to ultimate victory, and on the other hand, with the same weaponry (perhaps even more advantage to the "offensive" camp) turned into a trench war.

While technology, weaponry and doctrine play a part, its hardly the only factor.

This is all true, Gunfighter and Santa, but you're ignoring the OP. I'm just answering the OP. Just the strengths versus the weaknesses of offensive and defensive forces in war. No added factors - just offensive versus defensive forces.

It all depends on your objective. If you simply want to destroy a target there's not a defense in the world that can stop you. If you want to capture a target and have time on your side you can defeat any defence other than one who'd rather destroy the target than let you have it. If you need to capture a target and don't have the luxury of time you're in trouble.

@ Santa

Like I said, the first year of Korea very much resembled WWII, but it settled into a trench war because neither side had anything to gain, militarily or politically, by advancing ahead of their current positions.

GF is right. The first year of the Korean conflict was characterized by massive changes in territorial control. When peace talks began in 1951, China and the US put pressure on their respective patrons to limit their activities so negotiations could be held.