Why bother to attack in trench warfare?

Question

At least on the western front, trenches were heavily defended. Any charge was just suicidal, with heavy losses for the attacker and much smaller losses for the defender. As there is a big strategic advantage to be the defender and not the attacker, why bother launch an attack?

I understand that breaking the line of defense of the enemy and conquer their land grants you victory, but it's not the only way: the USA lost the Vietnam War, without being conquered. They withdrew because they endured too much of a loss.

Answer 1

Why bother to launch an attack?

First thing is to realize that strategic trench warfare in the Great War was not planned. It's something that happened to prevent being strategically outflanked. While trenches were used in individual battles prior, nothing like a deadlock on this scale had been seen nor even seriously considered before. Nor had the lethality of heavy machine guns, heavy artillery, and breech-loading magazine-fed rifles been accounted for.

Prior to the Great War, warfare was about small, professionally trained armies marching around the countryside in an attempt to trick the other side from accepting battle at a place of your choosing. The prior Franco-Prussian War of 1871 was fought with 500,000 men on each side compared to the tens of millions in the Great War. Battles would last a day or two and be sharp, decisive conflicts with one side holding the field and the other retreating. The largest battle of the war at Gravelotte lasted just one day. Warfare was still mostly a matter of keeping your forces acting as a unit, answering commands, and not running away. Victory came from taking the initiative, and crushing the enemy's morale. Waiting for your enemy to attack you gave them the initiative which would mean defeat.

The army leadership was not ready for a continent-spanning trench line bristling with machine guns and high explosives. They lacked the training and tactics to deal with it.

And we've never seen its like since. A single, continuous, fully manned line is too costly and too brittle for the pace of modern warfare. The Great War taught the armies of the world how to assault a line, and it also taught defenders how to be flexible rather than be rigid lest they be outflanked and bypassed. For example, Finland's Mannerheim Line was really a series of mutually supporting bunkers, dugouts, and trenches. If an attacker overruns any one position, they will take fire from multiple supporting positions. If multiple positions are overrun, the defenders fall back to another line.

For the French

If you're France and their allies, it's because you want the Germans out of France. The Germans aren't just going to just go away.

In any other situation you'd bypass a strong enemy position and cut off their supply. This avoids fighting the enemy where they're strong and forces them to come out to attack you. But the continuous line of trenches in the Great War made this tactical mobility impossible.

For the Germans

If you're the Germans it's a bit more complicated. At the beginning of the war they faced the nightmare scenario of being pulled into a two-front war with France on one side and Russia on the other, something which previous German leaders had sought to avoid. Their initial plan, the Schlieffen Plan, was to knock France out of the war before Russia could fully mobilize and threaten Germany; mobilization in those days took weeks or months. Then they'd rush their forces from France to meet the Russians.

It didn't work out that way. The Schlieffen Plan failed at First Marne and all hope of outflanking the Allied lines was lost in the Race To The Sea. When the Russians attacked East Prussia and Galicia Germany still had the bulk of its armies fully engaged deep in French territory.

At this point the Germans were sitting pretty on the Western Front. If they wanted, the Germans could have defended their captured French territory until they could negotiate beneficial terms with France. Meanwhile they'd spend their offensive energy fighting the Russians. This would be the same basic plan, just reversed: hold off France on French territory, knock out Russia, then send troops west to defeat France. Add to this that the Russians were now deep in German territory.

And in many cases the Germans did. Germans on the Western Front generally considered themselves there to stay: they were sitting on captured French territory and didn't need to go anywhere. German trenches were relatively lavish affairs. In contrast, the Allies always recognized that they could not simply defend. They discouraged improving the living conditions in the trenches because they were always considered temporary; they didn't want the troops to get to comfortable. Of course this lead to poor sanitation, demoralization, bad food, disease, and death.

This might have been a sound change in strategy, especially since the Eastern Front offered more options for traditional warfare focusing on mobility rather than attrition. But the Germans never fully adopted this strategy. A lack of strong leadership at the top can be blamed for this, Kaiser Wilhelm II was a mediocre leader at best. He had a strong bias against and rivalry with the British, wanting to challenge their world spanning empire. But also the belief that France was the "real enemy" and the Russians should be negotiated with. Rather than look at the military reality, they looked at it politically.

Instead they fought on both fronts simultaneously, see-sawing between fronts, strategies, and crises. Once the Russians were ejected from Germany in August 1914, the Germans focused on Russia in 1915 until they forced a great retreat. Rather than press their advantage, they went back to the "real enemy", France.

His chief of staff Erich von Falkenhayn held the belief that France was the traditional enemy of Germany, and that Germany and Russia had no real quarrel. This was the Germany political strategy prior to Wilhelm: keep Russia an ally to counter France. After the Western Front bogged down, Falkenhayn continued to believe they should defeat France militarily and negotiate with the Russians. In contrast Hindenburg and Ludendorff advocated attacking east. But Falkenhayn held the Kaiser's trust.

Verdun: the Germans attack to get the Allies to attack

Falkenhayn's big strategy was to attack at Verdun in 1916. He originally pitched this not as a breakthrough attack, nor the battle of attrition it turned into, but as a way to force the French to counter attack against strong German positions. Falkenhayn intended to swiftly capture the strong positions at Verdun, then sit back as the French threw themselves at him. He figured Verdun was so important to the French they must attack, and that the Allies must make additional spoiling attacks to try to distract the Germans. This would drain Allied reserves from the rest of the front, thinning the lines for a German attack elsewhere. So in that sense, he was attacking at Verdun to force the enemy to attack him.

It didn't work out that way. The Germans failed to take Verdun. The Allies failed to thin their lines to reinforce it. It turned into a meat grinder. Rather than realizing his strategy had failed and halting his attack, Falkenhayn now claimed Verdun was always a battle of attrition and continued attacking. Always with this hope that the Allies would be bled white. He was replaced as chief of staff by Hindenburg.

Too little, too late

Russia was eventually defeated in 1918. It did result in the Germans refocusing on France, though leaving far too many troops to garrison their conquered Russian territory. But by then it was too late. Germany and her allies had been bled white. US troops were arriving to bolster the Allies. When the German Spring Offensive hit the western front in 1918 they did so with new "stormtrooper" tactics. The Germans used fire-and-movement to break the stalemate and finally got their breakthrough. But they no longer had the manpower to exploit it.

Answer 2

The Allies attacked on the Western Front because of treaty obligations to do so; and because the Russians were beginning to suffer devastating losses, of both manpower and territory, quite early in the war.

These losses on the Easter Front would lead to the complete collapse of the Russian Empire itself through the spring and summer of 1917, followed early the next year by its withdrawal from the war. The Western Allies were attempting to prevent this.

The Western Allies were, rightfully, fearful of what the Germans could accomplish on the Western Front having once disposed of the Russian Army. Witness their spring 1918 offensive, which almost certainly would have broken the Western Front open if not for the availability of American forces to plug the gap at Chateau Thierry.

Note that the unsuccessful Gallipoli Campaign was another attempt to ease pressure on Russia (and provider her with Lend-Lease like supplies)

Here is a fascinating day-by-day animation of the entire war, world-wide.

---

Note that by late in the War, some commanders amongst the Western Allies had divined how to win battles without extreme casualties The French expended an estimated 150,000 casualties attempting to take Vimy Ridge during the Third Battle of Artois, yet the Canadian Corps successfully captured and held the ridge in April 1917 with barely 10,000 casualties. Sir Arthur Currie and Sir Julian Byng don't get enough recognition for this achievement.

Answer 3

The main problem is that having millions of armed men just sitting around in flooded ditches all day catching diseases and thinking about how much this sucks and they hate everyone involved in putting them there isn't really viable long-term either. For it to end, someone has to actually do something.

That being said, this was the germ of the original German idea for the Battle of Verdun. The hope was to quickly capture a strategic point so important that the French army would feel forced to throw themselves at the prepared German defenses to take it back. Falkenhayn claimed the main strategic objective wasn't the town so much as to destroy the French army during the inevitable counter-attack. This general approach (which the English and British eventually countered with their own) is called Attrition Warfare.

Answer 4

Soldiers charging into machine gun fire has become a rather infamous image of WW1. However, the MG's full power was not yet realised at the start of the war and the Great War only devolved into trench warfare after the first battle of the Marne (Sep 1914) - before that, it was a relatively dynamic kind of warfare with successful attacks. Furthermore, as the Germans were the invading party and occupied a part of France and Belgium, the Allies saw a greater need to push them out, hence the 'obligation' to carry out more offensives to push the enemy out of France & Belgium (in contrast, the Germans only launched a few big offensives, such as Verdun and the 1918 Spring offensive).

It's important to note that while the start of the war saw generals and officers completely detached from military reality, effective tactics were developed in the course of the First World War that gave offensives a much higher chance of success, and that not all battles consisted of 'blast the enemy to pieces, then charge en masse'. Technology advanced as well in reponse to the grim reality of war. Newer doctrines included:

• the creeping barrage

• combined arms (artillery + inf + planes) and new operational tactics, most famously put to good use in Cambrai (1917)

• Artillery sound ranging

The major problem in the trench war was in fact not breaking through - that could and did happen- it was exploiting that breakthrough. Infantry advancing without artillery usually would ground to a halt. It's only in WW2 that self-propelled artillery and tanks really made their debut.

Answer 5

At a tactical level, you attack because it works. Passchendaele, the Somme, Verdun, Artois...pick any battle of the Western Front, and odds are good that the attacking force managed to kick the defenders out of their forward trenches and advance a few hundred to a few thousand meters past the old front lines. Battles that didn't see initial success are few and far between.

The protracted carnage of trench warfare mostly comes from fighting after the initial surge of a battle. Once the infantry outrun their artillery support, it becomes much more difficult for them to defeat entrenched opponents. Additionally, they don't have field fortifications to defend against a counterattack, and without trenches, they're vulnerable to the defenders' artillery fire.

A large part of the success of the Hundred Days' Offensive at the end of the war came from recognizing how attacking a trench line works. Unlike the earlier attempts to turn initial success into a "decisive breakthrough", the Allies used a rapid series of limited-objective attacks to drive the Germans back.

Answer 6

Question: Why bother to attack in trench warfare?

Short Answer:
Because the military leaders of both sides informed by hundreds of years of hard learned experience believed that troops on offense always had the advantage over troops on defense. It was called the cult of offense. The belief in offense over defense was so entrenched in military philosophy even as massive casualties piled it's proponents were characterized with cult like loyalty. The reason for this loyalty to offense was for several centuries history taught that troops on the offense always inflicted more damage than troops on defense. Thus the only reasonable defense was counter attack ( offensive defense). Only technology changed and now due to improvements in fire arms ( wide use of riffles rather than muskets, and most importantly in WWI the wide use of the machine gun), fortified defenses now rather than offense had the advantage.

Longer Answer:
Experience and study of the military arts blinded military leadership to what they were experiencing. Recent changes in technology and tactics had made offensives in the fashion militaries were used to conducting unacceptable costly. It took several years of costly losses trying to attack entrenched machine guns with infantry to learn the lesson that military truisms which went back before the Napoleonic Wars were no longer valid.

History which generally guides military practices (learn from previous mistakes) is always blind to the latest innovations or tactics. Worse, during WWI historical precedent informed commanders offense was the quickest path to victory. Although already proven wrong in the British Crimean War and American Civil War; conventional wisdom (see Cult of the Offensive) in WWI was offense and massed infantry would overwhelm defensive formations. In the US Civil war and Crimean war conventional wisdom did not account for the Minié ball. In WWI conventional wisdom did not account for the machine gun.

Volley Fire
Despite the development of light infantry tactics and the increased effectiveness of firearms during the 19th century, -as was witnessed during the American Civil War and the Franco-German War-, the linear tactics, with massed volley fire, remained the basics of European warfare up to World War I.

In Crimean War(Battle of Balaclava) and the US Civil War(Picket's charge) the Minie ball, which enabled the wide use of rifles over muskets with their vastly improved accuracy and range (4 times the range) turned the Napoleonic tactics of platoon firing into a then unprecedented bloodbath. In WWI the machine gun turned the same tactics of volley fire into mass suicide.

The Bullet which Changed History
Almost as soon as the war(US Civil War) ended, historians began to study the factors that contributed to so much bloodshed – more than 200,000 killed and nearly 500,000 wounded – and concluded that the introduction of the rifle musket was the primary cause of the staggering casualty rates. And not without reason: the rifle musket combined the best features of the smoothbore musket and the Kentucky flintlock rifle. It could be loaded quickly and easily – an experienced soldier could load and fire up to four rounds a minute – while its long, grooved barrel gave it an effective range up to four times that of a smoothbore, with similar improvements in accuracy.

The Minié ball made rifles practical. Now instead of a specialized weapon reserved for sharp shooters and snippers, every man on the battle field could use a highly accurate long ranged riffle without sacrificing loading speed or reliability. The result was casualties skyrocketed as the tactics used for troops carrying smooth bore muskets were still employed for troops now carrying riffles with 4 times the effective range and to my mind even more dramatic improvements in accuracy.

The innovation of a riffle is it has grooves in it's barrel which spin the round as it is discharged. The spin gives the round both improved distance and vastly improved predictability in flight(accuracy). The often unstated ancillary detail is that in order for the round to pick up those grooves and thus receive these benefits, the diameter of the round must be extremely tight with the diameter of the barrel. (modern breach loaded rifles and pistols the rounds are larger than the barrel). This is why bullets are made out of soft metal. The gunpowder forces the overly large round down the narrow barrel and the curves give it the spin. This made riffles exceedingly slow and cumbersome to load, and unsuitable for being the primary infantry weapon until the advent of the Minié ball. The Minie Ball was small when being loaded and it's hollow tail expanded when fired to pick up the grooves in the barrel.

"Minié ball"
The Minié ball, or Minni ball, is a type of muzzle-loading spin-stabilized rifle bullet named after its co-developer, Claude-Étienne Minié, inventor of the Minié rifle. It came to prominence in the Crimean War and American Civil War. The development of the Minié ball was significant because it was the first projectile which was small enough to be easily put down the barrel of a rifled long gun. Rifling – the addition of spiral grooves inside the gun barrel, which imparted a spin to the bullet – greatly increased the range and accuracy of the gun. Prior to the Minié ball, balls had to be jammed down the rifle barrel, sometimes with a mallet, and after a relatively small number of shots, gunpowder residue built up in the spiral grooves, which then had to be cleaned out.1 Both the American Springfield and the British Enfield rifles – the most common rifles used during the American Civil War – used the Minié ball.

Why did trenches even occur? Because frontal approach of machine gun positions caused so many casualties they couldn't mass enough troops and keep them alive long enough for a proper offensive. Then they figured out that even massed overwhelming infantry emerging from trenches close to the enemy positions still stood no chance against machine guns the stalemate which was WWI began in earnest.

Trench Warfare
Trench warfare occurred when a revolution in firepower was not matched by similar advances in mobility, resulting in a grueling form of warfare in which the defender held the advantage...

.. Machine guns at the beginning of WWI weighed whopping 136.5 pounds. Not a problem for defensive troops in pre-fortified positions; a huge incumberance however for advancing troops.

Machine Guns
Machine guns inflicted appalling casualties on both war fronts in World War One. Men who went over-the-top in trenches stood little chance when the enemy opened up with their machine guns. Machine guns were one of the main killers in the war and accounted for many thousands of deaths.

Crude machine guns had first been used in the American Civil War (1861 to 1865). However, tactics from this war to 1914 had not changed to fit in with this new weapon. Machine guns could shoot hundreds(600+) of rounds of ammunition a minute and the standard military tactic of World War One was the infantry charge. Casualties were huge. Many soldiers barely got out of their trench before they were cut down.

.

By 1917, the Germans were reporting that the majority of their small arms ammunition, 90% to be exact, were going into the chambers of their machine guns.

Long story short. Practical military experience historically speaking is a see-saw; for a time the defense will have the advantage and offensive actions bare the primary costs for battles ( see feudalistic middle ages with their great stone castles, or see the machine gun in WWI ); and then everything changes. Some new technological innovation or tactic and the offense has the advantage. Now it's near suicide to be on the defense ( see introduction of cannons and how it changed castles or see the introduction of the Tank and the German Blitzkrieg). The flip side of this is most armies which fight wars, begin their war using the outdated and often suicidal tactics that would have worked well if they used them beginning their last war. ( see WWII, battle of France and the Maginot Line).

Cult of the Offensive
The cult of the offensive refers to a strategic military dilemma, where leaders believe that offensive advantages are so great that a defending force would have no hope of repelling the attack; consequently, all states choose to attack. It is most often used in the context of explaining the causes of World War I and the subsequent heavy losses that occurred year after year, on all sides, during the fighting on the Western Front.

Under the cult of offensive, military leaders believe that the attacker will be victorious (or at least cause more casualties than they receive) regardless of circumstance and so defense as a concept is almost completely discredited. This results in all strategies focusing on attacking, and the only valid defensive strategy being to counter-attack.

.

During WWII with the advent of new tactics using massed armor this paradigm of offense having the advantage over defense would again exert itself General George Patton would say "Fixed fortifications are a monument to the stupidity of man." Because in WWII this became true again.

We are still going through this pattern today where for a time offense has the advantage and then due to technological advances and new tactics defense has the advantage... In 2006 the Israeli's fought Hezbollah in southern Lebanon. Israel used the tried and true Armor attack supported by air superiority, artillery and infantry. Basically the same tactics Germans used against France and the same tactics Norman Schwarzkopf used against Saddam. Only in 2006 Hezbollah had an answer. Pre fortified tunnels, sophisticated American and Russian anti tank and anti personal missiles. First defeat in Israel's short history of overwhelming militaries victories.. or at least the first time any Israeli Army has left the enemy in the field and retired.

Haaretz Israel’s Second Lebanon War Remains a Resounding Failure
The Israel Defense Forces had fought Hezbollah and Palestinian groups before, but this time it faced an enemy that avoided direct clashes while tailing it at every opportunity and firing Katyusha rockets at the Galilee until the war’s last day. The fact that the IDF couldn’t bring the campaign to a decisive conclusion created great frustration in the government, among the public and in the army itself.

.

Washington Post 2006 War Called a 'Failure' for Israel
But the panel(Winograd Committee, appointed to examine Israel's conduct of the 2006 war by then Israeli PM Ehud Olmert) did conclude that the war "was a big and serious failure" for Israel, Eliyahu Winograd, the retired judge who led the committee, told reporters.

.

NyTimes A Disciplined Hezbollah Surprises Israel With Its Training, Tactics and Weapons
Hezbollah, Mr. Goksel says, has clear tactics, trying to draw Israeli ground troops farther into Lebanon. “They can’t take the Israelis in open battle,” he said, “so they want to draw them in to well-prepared battlefields,” like Aita al Shaab, where there has been fierce fighting.

He added: “They know the Israelis depend too much on armor, which is a prime target for them. And they want Israeli supply lines to lengthen, so they’re easier to hit.”

Israeli tanks have been struck by huge roadside bombs planted in expectation that Israeli armor would roll across the border, said one tank lieutenant, who in keeping with military policy would only give his first name, Ohad.

.

Hezbollah’s Creative Tactical Use of Anti-Tank Weaponry
Among the many aspects to be investigated is the vulnerability of Israel’s powerful armored corps to small, hand-held, wire-guided anti-tank weapons. Indeed, Hezbollah’s innovative use of anti-tank missiles was the cause of most Israeli casualties and has given the small but powerful weapons a new importance in battlefield tactics.

---

Sources:

• Volley Fire
• The Bullet which changed the World
• Pearl Harbor, Thunderfish from the sky
• "Minié ball"
• Machine Guns
• How The Machine Gun Changed Combat During World War 1
• Cult of the Offensive
• Israel’s Second Lebanon War Remains a Resounding Failure
• 2006 War Called a 'Failure' for Israel
• A Disciplined Hezbollah Surprises Israel With Its Training, Tactics and Weapons
• Hezbollah’s Creative Tactical Use of Anti-Tank Weaponry
• Wiki: Trench Warfare
• Battle of the River Amnias

Answer 7

Politics

In World War 1 the British Army was asking themselves that question with the generals being unable to come up with an answer. There preferred plan was to wait and send their forces into Germany.

France wanted the British forces in France, and so because of that so did the British politicians.

There was a plan to avoid the trench warfare that happened, Britain was secretly building three hundred tanks, which would have dramatically changed the battle of the Somme. But again politics.

Due to the attacks on Verdun the schedule was brought forwards by three months. Leaving Britain with a half trained army, no tanks and much less French troops to support them.