So you're at war, and you're preparing for a big offensive that will finally turn the tide in your favor. You've drawn up A Simple Plan to secure victory, your Redshirt Army far outnumbers the enemy Mooks defending whatever city, bridge, fortress, or other strategical MacGuffin you mean to seize, and they are equipped with the latest in artillery, tanks, aircraft, and small arms. You are all but assured that the upcoming battle will be a Curb-Stomp Battle in your favor... and so, you confidently announce: "Nothing Can Stop Us Now!" After all, What Could Possibly Go Wrong?
Quite a lot, actually.
This trope is about overconfidence in a war situation, be it about the entire war or a specific attack – the point is that what is assumed beforehand to end in a quick and easy victory will turn into a long and grueling battle (or even a quick and easy defeat) instead. If it goes really wrong, it could end up as a Shocking Defeat Legacy, thus making any statements of confidence about the matter (such as "Tomorrow we'll have coffee in Huesca" in the page quote) a lot Harsher in Hindsight.
This is very often Truth in Television. Getting your troops "home by Christmas" has historically been a highly sought-after objective for military forces, particularly those fighting in extreme latitudes; not only is it an obvious morale booster to get the boys home in time for turkey dinner and presents under the tree, but it's also desirable from a practical standpoint, given as how winter is an especially harsh and brutal time to be outdoors, and any army that marches in the snow is virtually guaranteed to rack up significant losses from the cold alone.
Compare to It Seemed Like a Good Idea at the Time. Not to be confused with Hurrying Home for the Holidays, a plot where a character has trouble getting home for the holidays, or Christmas Rushed, which is when the production of a piece of media is compromised to ensure its release before a date not inherently related to the work.
- Along Came a Spider: The Clans' leaders plan assumes that they'll require only a fraction of their forces to sweep across the Inner Sphere due to their superior training and weapons. It doesn't quite work out that way.
- The Negotiations-verse fanfics usually have this as the disposition of Equestrians at the start of the war. The war proceeded to go on for far longer than that, and eventually humanity reverse-engineered magic enough to get the upper hand.
- Discussed in the opening narration of A Bridge Too Far: 'The plan, like so many plans in so many wars before it, was meant to end the war by Christmas and bring the boys back home.' See above link for Operation Market Garden, the Real Life example on which this film was based.
- In Stalingrad, one of the German soldiers says they'll take the city in three days. In three weeks, the city still won't have fallen. In three months, most of the soldiers will be dead.
- Lampshaded by Rhett Butler in Gone with the Wind: "Poor devils. They were gonna lick the Yankees in a month." In an earlier scene, while everyone is boasting that they'll defeat the North in a single battle, Rhett correctly asserts that they won't be a pushover. The North has factories, shipyards, coal mines, and a powerful navy, while the South has "cotton, slaves, and arrogance."
- General Hancock makes a similar comment about the expected length of the war from the Union perspective in Gettysburg.
- In The Worlds Fastest Indian, which takes place in the mid-60s, Burt Munro picks up a hitchhiking American airman who's on leave. The airman describes how they're going to start using something called "Agent Orange" in Vietnam, and it should end the war in six months.
- This happens in Troy with the Greeks being confident that the titular city will fall within days. Instead, it takes far longer than that, and many Greeks are killed before Troy falls. However, the condensed time frame omits the full ten-year-long conflict.
- In Octopussy, Soviet General Orlov tries to convince the Politburo that the Red Army can win a conventional war against NATO within five days.
- Discussed in Australian film The Lighthorsemen (1987). When a soldier snaps at the New Meat, "What do you know about war?", the man snarks back that at least he didn't think it would be over by Christmas.
- They Shall Not Grow Old: Actual veterans of WWI recount in voice-over how they figured that a British soldier is worth 10 Germans and so the war would be over quickly. One veteran recalls how worried he was that Britain would win before he saw any combat.
- 1917 has the characters bitterly acknowledging this, noting that their commanders claimed that they'd be home by Christmas—and now it's April, and they're still fighting. There's also rumblings that there's going to be another big push and this is going to be the one that finally breaks the Germans. They're half-right; the Battle of Arras happened two days after, and it did push the lines a fair bit further, but the war dragged on regardless.
- The Resistance Banker. La Résistance are ordered by London to shut down the railway network with a national strike. They approach the man in charge of the Dutch national railways who assures them they have an emergency fund put aside to pay the wages of the striking workers for the few weeks to a month it will take the Allies to liberate Holland — this is in September 1944. The protagonists exchange a skeptical look and set about organising a more realistic fund, which unfortunately requires them to acquire millions of guilders.
- Coming Home: In early 1968, Captain Bob Hyde is told by a superior officer that he is lucky to be getting in on the combat in Vietnam while has the chance, because the Americans will soon be victorious and the war will be over. "Word is that Charlie's shot his wad."
- At the start of the Civil War arc in Cromwell, Prince Rupert tells his uncle King Charles that they'll have defeated the Roundheads within a week. While he wins the battle that follows pretty easily, Cromwell would survive to found the New Model Army and defeat the Royalists over the course of a four year war.
- Lampshaded in the Black Chamber novels by S. M. Stirling, which is set in 1916. A comment is made that the last time anyone thought that the Great War would be over and everyone home by Christmas was December 24th, 1914.
- In the Discworld book Jingo, the Upper-Class Twits leading the Morporkian army thought that they'd have a jolly good time teaching the Klatchians a lesson, that the enemy would run at the sight of their steel, and that they'd be home by Hogswatch. This despite the fact that they were badly armed, hopelessly outnumbered, and the Klatchians who actually saw their steel tended to start sniggering. Later in the book, one character bemoans that "We were going to sail into Klatch and be in Al-Khali by teatime, drinking sherbet with pliant young women in the Rhoxi," mirroring the confident statements of some WWII soldiers that "We'll be drinking coffee in Berlin by teatime."
- The Emigrants: The last book is set during the American Civil War. At the beginning of it, the Minnesotan settlers are optimistic that it will end in a few months with victory for their side. Instead the Union suffers defeat after defeat and the war drags on.
- Goodbye, Mr. Chips has a scene set in 1914 where one of Mr Chipping's students asks him if he thinks the war will last long. Chips says he thinks the Germans are already beaten and just don't know it yet, and that the whole thing will be over by Christmas. He then jokingly asks if the boy was thinking of joining up, not knowing that by the time the war grinds to its conclusion the same boy will have joined up and died in action.
- Greenmantle begins in December 1915, so even the most optimistic don't believe the War will be over by Christmas, but while traveling through Germany the protagonist overhears a soldier confidently asserting that it will all be over by next Christmas.
- The page quote is a fine example from the Spanish Civil War, as recounted by George Orwell in Homage to Catalonia.
- Honor Harrington: In The Short Victorious War, The People's Republic of Haven leaders decide to resort to war against Manticore. A short, victorious war, they believe, will both distract the proles from their current economic problems and allow them to use the riches of the Manticore system to prop up their welfare state. Needless to say, the war is a disaster for Haven and ends up lasting for almost 20 years. They even lampshade this with a quote from V.K. Plehve (see the Real Life section below), providing the Title Drop for the book in the opening epigraph, followed by a quote from Robert Wilson Lynd:
"The belief in the possibility of a short decisive war appears to be one of the most ancient and dangerous of human illusions."
- After the break-out from Normandy and a two-hundred-mile blitzkrieg that took British forces to the Dutch border against a disintegrating German Army, the tank crews of Mailed Fist felt they could well be home by Christmas 1944. This hope was dashed by Monty's Arnhem failure and shattered by growing German resistance.
- In the opening chapter of Without Remorse, Colonel Zacharias has just finished his bombing run and is heading back to base, thinking that his tour will be over soon and he'll be home from Vietnam by Christmas. He promptly gets shot down and spends the next fifteen months as a prisoner of war.
- Andrey Livadny's Dabog describes the start of what would become known as the First Galactic War (to be fair, though, the scale of the war is far from "galactic", being limited to a few dozen systems and involving only humans). Earth Alliance President John Winston Hammer decides to send a powerful strike fleet to perform a preemptive strike on Dabog, one of the more prosperous of the colonies, in order to show all the colony worlds that Earth is the center of human space. Hammer's goal is to force the colonists to accept the millions (if not billions) of people that need to be resettled in order to relieve the overpopulated Earth. At this point, the colonists don't even know about Earth Alliance (they're all Lost Colonies, who haven't yet regained contact with their homeworld). While the fleet is on the way, the troops boast about how they'll beat those "stinking" colonists silly for daring to hog their lands, while Earth is an overpopulated hellhole. The EA admiral is also confident that there's nothing the colonists can do against such an overwhelming force. The fleet arrives in Dabog orbit and "announces" itself by nuking two large cities on opposite sides and landing troops. Unfortunately for them, the Dabogans had to reinvent certain pieces of technology to handle the planet's harsh climate and large dinosaur-like predators. This includes developing Walking Tanks with superior mobility that turn out to far outclass the more traditional vehicles used by EA troops. After being forced off the planet by "a bunch of farmers", the furious admiral orders the planet sterilized with massed nuclear bombardment, hoping that the other colonies will see this as a valuable lesson. Instead, the other colonies band together and form a unified force that ends up resisting the EA juggernaut for nearly 5 decades and eventually takes the fight to Earth itself. On the one hand, Earth ends up being no longer the dominant force in human space, being replaced by the Confederacy of Suns, based in the colonies, on the other, Hammer's initial goal of reducing Earth's population ends up being reached, just not the way he intended. The massive casualties on both sides and the steady flow of people fleeing the technological destruction results in most of Earth's population either dying or leaving. Centuries later, Earth is populated by a few hundred million people with most of its cities are abandoned and overgrown. Meanwhile, the name "Dabog" stands for defiance in the face of overwhelming odds, and the still-radioactive planet remains the silent monument to the fallen.
- Played for Laughs in the Nursery Crime novel The Fourth Bear. The QuangTech corporation has scheduled the opening of their World War One simulation theme park SommeWorld for Christmas, and construction is badly behind schedule, as is thematically appropriate.
- In the second Trail of Glory book, President Clay decides that a short, victorious war against the Native American/Freed Slave nation of Arkansas is the perfect thing to shore up his public support after gaining the Presidency through backroom deals in Congress despite only getting about a sixth of the popular vote. Every veteran soldier who knows the ground and the quality of Arkansas' army privately notes that while victory is at least theoretically possible, "short" is out of the question.
- The final episode of Blackadder Goes Forth (the fourth and last Blackadder series, set during World War I) features characters making remarks like "It's ice cream in Berlin in 15 days", "See you all in Berlin for coffee and cakes", and "We'll be sucking sausages in Berlin by teatime!" about the upcoming battle. Eventually Blackadder hangs a lampshade on this by snarking, "I hope their cafés are well stocked; everyone seems determined to eat out the moment they arrive."
- Studio 60 on the Sunset Strip: during a two-parter where a cast member's brother is being held hostage in Afghanistan, we see a Flash Back, during which the President of the network (who was only a VP then) opines that the war will be over in a month.
- The Battle of Serenity Valley in Firefly was assumed by Alliance command to be an easy victory. Though the Independents would ultimately lose the battle due to massive Alliance air support, the browncoats were nonetheless able to hold the Alliance for far longer than anyone thought possible (the fact that the Alliance had to call in the air support was a victory of sorts). Unfortunately, it's implied that the "victory" in the valley was ultimately disastrous for the Independents, who surrendered not long after.
- In the NCIS episode "One Shot, One Kill", a Marine recruiter tells a pair of nervous potential recruits, "What with boot camp, S-O-I, follow on schools... we're talking over a year and a half of training. Iraq will pretty much be over by the time you boys graduate." The episode aired in February of 2004, and Reality Subtext ended up putting that assertion squarely into this trope.
- In the opening scenes of the German miniseries Unsere Mütter, unsere Väter, five friends have one last drink in Berlin. Two of them are leaving for service in Operation Barbarossa, one of them has volunteered to be a nurse on the front, another is an aspiring singer, and the last one is Jewish. They leave, hoping that by Christmas, Russia will be crushed and all of them will be reunited in that bar. The war ends four years later, Germany is defeated, and two of the friends don't make it back.
- Star Trek: Deep Space Nine: The Dominion found its hopes for a quick victory smashed by being cut off from reinforcements. Then after the Breen join, they again start to dream of a quick victory, but again the situation is turned around. On the other side of the battlefield, Gowron also kept thinking his incompetent tactics would lead to swift victory.
- There are a few examples of this in early episodes of Enemy at the Door, with the Germans fresh from rolling over France. In "Steel Hand From the Sea", Reinicke expresses confidence that they will be in London before the summer's end.
- Anne Frank: The Whole Story. When announcing the D-Day landings, the BBC assures those living in occupied Europe that "1944 will be the year of your liberation!"
- In the TV movie Shackleton, one sailor says that surely World War I won't last past Christmas. Another says that might be too optimistic, but that it will surely be over by the time they get back from the Antarctic. Two years later when Shackleton finally reaches the settlement in South Georgia he asks who won, only to be informed that the war is still going on and millions have died in it.
- Referenced frequently on M*A*S*H by the main characters. As the war dragged on, one episode actually has them celebrating the New Year and praying that the war will be over by the next New Year. One entire year later and they're still there.
- "I'll Be Home for Christmas", first recorded in 1943 by Bing Crosby, was originally written from the perspective of a World War II serviceman who writes to his family about how he'll be home by Christmas. At the end of the song, he repeats "I'll be home for Christmas"... before adding "if only in my dreams", admitting it's unlikely he really will be home by Christmas.
- Subverted in the anti-war Protest Song "Stop the Cavalry" by Jona Lewie – the line "Wish I was at home for Christmas" not only shows the narrator realizes how unlikely it is but also ensures this song will be played year after year in winter.
- The BattleTech universe certainly has seen its share of this trope. Two large-scale examples — smaller ones abound, but these are really just perhaps the two biggest ones in the entire history of the setting — would be the Reunification War (as initially viewed by the newly-minted Star League) and the Clan invasion of the Inner Sphere (from the original point of view of the Clans); needless to say, neither actually worked out that way. The Clans are a particularly noteworthy example in that they started out from a position of considerable strength, with significantly better equipment than the Inner Sphere powers and in theorynote the ability to manufacture replacement equipment faster, but managed to completely squander that advantage through a mixture of Suicidal Overconfidence and Honour Before Reason and lose so spectacularly that their entire society and way of life came close to being destroyed. (Albeit mostly by the second war they started with each other over whose fault it was.)
- Often happens in Real-Time Strategy or Turn-Based Strategy games when a player attacks another player or an AI opponent with an army that is slightly too small.
- The Covenant believed that their war against humanity would be a short venture. Instead, the war would drag on for another twenty-seven years, and contribute to a series of events that would divide Covenant society to the point of Civil War.
- In the opening cutscene of Halo Wars, Cutter notes that humanity themselves initially expected to easily retake Harvest from the Covenant. Instead, the Harvest campaign became "five years of Hell".
- The opening of Hogs of War, as with any other War Tropes parodied, literally ends with this: "With some luck, it will all be over by Christmas". The obligatory Harsher in Hindsight part comes when, in the ending, we find out that the glasses-wearing soldier seen in the opening got dumped by his girlfriend and is now homeless due to his house having been destroyed during the war.
- As revealed by backstory fluff, the Taiidan Empire from Homeworld attacked Kharak in the belief that a short victorious war against the surviving Hiigarans, ancestral enemy of the empire, would have quelled the internal opposition by both finishing the job with their most hated enemy in history and showing the might of their all-powerful emperor. Not only the destruction of all life forms of Kharak triggered the revolution and civil war (as the people realized their ancestral Hiigaran enemies had forgotten the treaty forbidding them from using hyperspace technology ever again that they had broken), but some Kushan, the descendants of the Hiigarans, had survived, and would cause the collapse of the Taiidan Empire by killing the emperor in battle. On a smaller scale, the fleet that laid waste to Kharak met with much more opposition than expected and was forced to withdraw before destroying the sleeper pods in orbit. The Kushan mothership ended up catching up to the damaged fleet and obliterated it in retaliation for Kharak.
- In Dragon Age: Origins, Cailan is confident that his forces and the Grey Wardens will be able to stop the Blight in one epic battle at Ostagar. That...doesn't end up happening, due both to King Cailan's stupidity and Loghain's treachery. The trope is also inverted by the end. Blights usually last for years or even decades — the first Blight lasted nearly two centuries because the Wardens hadn't yet discovered how to end Blights. The Warden and their allies end the Fifth Blight in less than one year.
- The The Legend of Heroes: Trails of Cold Steel series tends to be accurate in the timeline of these boasts, but wrong about everything else:
- At the beginning of the second game, the rebels are certain that the war will be over within a month or so (to be fair, the surprise attack they launched at the end of the first game was so successful that they had good reason to believe so). A month later, the rebels have lost the war. Coincidentally, the war ended on New Year's Eve, so everyone was almost home by Christmas (though there is no explicit mention of that holiday in the game since Christianity doesn't exist in that universe).
- In the fourth game, a new war with Calvard is announced, and the Erebonian government declares that they will have victory within three months. The war ultimately lasts two days, after which Emperor Eugent recovered from his injuries sufficiently to order the army to stand down, declaring that the man who shot him wasn't a Calvardian agent and thus there were no grounds for an invasion.
- Referenced and lampshaded in Rebel Inc. where selecting the Home By Christmas cheat activates the Harder Than Hard mode.
- In the story "Heart of the Lion" from The Wulf Archives, the White Empire attempts to conquer the Veldt Lands in order to enslave the natives. This "quick campaign," led by an arrogant Upper-Class Twit by the name of Lord Heatham, fails miserably — less than half of the forces fielded actually make it to the battlefield due to adverse sea conditions and local diseases on land, and the battle with the Sholanti ends with everyone on the battlefield (except the protagonist) slaughtered to a man.
- In The Simpsons episode "Tales from the Public Domain," Homer starts the Joan of Arc story by saying the Hundred Years War was originally called "Operation Speedy Resolution."