很多前来游玩的外国友人一直持有怀疑的态度，对于长城在历史文化中的战争功效一直持有怀疑的态度。在他们心中就感觉这无非是在山上修建的一条带有护墙的山路而已，军事作用真的那么大吗，能挡住敌人的火炮吗？在海外问答网站Quora上，美国网友提问道：中国的长城这么低矮，它达到预定的作用了吗？这引起各国专家网友的热议，我们看看他们的观点。

问题

海外网友帕崔克的回答

From the Qin Great Wall (the First Emperor of Qin tried to connect the city walls of the Warring States Period into a continuous wall) to the 20th century, the Great Wall was never strategically defeated by the invaders militarily. However, this does not mean that the wall has been airtight for 2300 years.

从秦长城（秦始皇试图将战国时期的城墙连接成一堵连续的墙）开始到20世纪，长城从未在军事上被侵略者战术性失守。然而，这并不是说这堵墙在其2300年的历史中密不透风。

As there are vast grasslands in Mongolia and Siberia today, most of these "barbarians" have ridden on horseback in the past several thousand years; Most of them are hunters/gatherers/herders, so they usually have better cavalry.

由于今天的蒙古和西伯利亚有大片草原，过去几千年中，这些“野蛮人”大多骑在马背上；他们大多是猎人/采集者/放牧者，因此，他们通常拥有更优秀的骑兵。

Chinese civilization is based on agriculture. There are not many horses on the traditional Chinese land, so the main defensive units of the Chinese are infantry. The Chinese, with a few exceptions, are usually not good at training large numbers of high-quality cavalry to fight against the barbarians in the north.

中国文明以农业为基础。传统的中国土地上没有很多马，因此，中国人的主要防御单位是步兵。中原人，除了少数例外，通常不太擅长培养大批高素质的骑兵来对抗北方的野蛮人。

Since there are no natural boundaries such as mountains, rivers and so on, the vast land needs to be protected, and the Central Plains is easily controlled by the "barbarians" in the north. Because of their quick action, they can easily attack any place in the northern plains of China without warning or response time.

由于没有山川河流等自然边界，广袤的土地需要保护，中原很容易被北方的“野蛮人”所控制。由于行动迅速，他们可以轻易地袭击中国北方平原的任何地方，几乎没有预警，也没有反应时间。

Worse than the large-scale organized attacks (such as the looting of China's feudal capital around 800 BC) is the small local attacks that the "barbarians" tribes could not prevent. These small-scale attacks are difficult to counter. Once it happened, the Central Plains Dynasty had no choice but to tear up the peace agreement with the "barbarian leader" and risk an all-out war, or let its citizens become mermaids, which made it difficult to uphold justice for the loss of their subjects' lives/property.

比有组织的大规模袭击（如公元前800年左右，中国周朝首都曾遭到洗劫）更糟糕的是“野蛮人”部落防不胜防的小型局部袭击。这些小规模的袭击很难反击。一旦发生，中原王朝没有选择，要么撕毁与“野蛮人首领”的和平协议，冒着全面战争的风险，要么让其公民任人鱼肉，难为其臣民的生命/财产损失伸张正义。

Setting up a defensive wall has two effects. First of all, small-scale attacks make the aggressors very dangerous. It is not because the city wall itself can prevent "barbarians" from rampaging in the city wall. It is precisely after the plundering in the city wall that the Chinese garrison has the means to gather troops and block the gate, making it difficult for them to return to the prairie safely.

竖起一堵防御墙有两个效果。首先，小规模袭击让侵略者处境变得非常危险。并不是因为城墙本身可以防止“野蛮人”在城墙内肆虐，正是在城墙内的掠夺之后，中国驻军才有办法集结兵力，封锁大门，让他们很难安全返回大草原。

Second, even if a large army (mainly composed of cavalry) tries to enter the city wall, the offensive forces need to reserve enough troops to fight with the defenders on the way back from the city wall, leaving only a few people to encircle the city. Therefore, when the national strength of the Central Plains was weak, the northern nomads might launch attacks around the cities. The people of the Central Plains were sure that these "barbarians" would eventually leave, and they were safe inside the city walls.

第二，即使大规模军队（主要由骑兵组成）设法进入城墙，进攻部队也需要储备足够的兵力，以便在城墙撤退的路上与守军作战，从而只能留下很少的人员来围困城市。因此，在中原国力较弱的时候，北方游牧民族可能会在城市周围发动袭击，中原人有把握这些“野蛮人”最终会离开，他们在城墙内是安全的。

China was completely conquered by the "barbarians in the north" twice in history, so it left a "false" impression that the Great Wall was invalid.

中国在历史上曾两次被“北方少数民族”彻底征服，因此，给人留下了“虚假”的印象，认为长城是无效的。

The first time was when the Mongols defeated the Song Dynasty (1279 AD). Most people, even the Chinese themselves, do not remember the northernmost position of the Song Dynasty. Even at the peak of their national strength, they never reached the Great Wall. Without the protection of the city walls, the Song Dynasty was always in a weak position, although it had a standing army of one million people. It is considered to be one of the weakest dynasties in Chinese history, although it was the most advanced civilization of mankind at that time.

第一次是蒙古人打败了宋朝（公元1279年）。大多数人，甚至中国人自己，都不记得宋朝的最北端的位置，即使在其国力顶峰时期，也从未到达长城。没有城墙的保护，宋朝尽管有一百万人的常备军，但始终处于弱势地位。它被认为是中国历史上最薄弱的王朝之一，尽管它是当时人类最先进的文明。

The second conquest of the Central Plains was in 1644 when the Qing army entered the pass. Although the Ming Dynasty hardly had enough strength to deal with the Manchu, the Great Wall itself would not fall strategically until Wu Sangui, one of the most important garrison generals, heard that the Ming Dynasty emperor he served was actually killed by rebels.

第二次征服中原是在1644年清军入关。虽然明王朝几乎没有足够的力量来对付后金，但直到最重要的卫戍将领之一吴三桂听说他所服务的明朝皇帝实际上被叛军杀害，长城本身才会战略失守。

In short, the Great Wall is very effective because:

简而言之，长城非常有效，因为：

-It limits the attack points to (relatively speaking) several gates, rather than any arbitrary place on the northern border of China;

-它将攻击点限制在（相对而言）几个大门，而不是中国北方边境的随意任何地方；

-It gave the garrison in the Central Plains, mainly infantry, a chance to fight against nomadic invaders, mainly cavalry;

-它给了以步兵为主的中原驻军一个对抗以骑兵为主的游牧侵略者的机会；

-In fact, it eliminated small-scale attacks within the city wall, because the Chinese garrison could block the city gate and deal with the invaders on China's own territory;

-它实际上消除了城墙内的小规模袭击，因为中国驻军可以封锁城门，在中国自己的地盘上对付入侵者；

-The city wall is not airtight. This may be a major misunderstanding that the Great Wall is invalid. The wall itself cannot prevent large-scale incursions. However, even if there is a huge army, the invading troops either need to save troops to keep the gate open or need to keep enough strength to fight back. Therefore, the Great Wall makes it relatively difficult to encircle cities within the wall.

-城墙不是密不透风的。这也许是一个主要的误解，认为长城是无效的。隔离墙本身无法阻止大规模入侵。但即使有庞大的军队，入侵部队要么需要节省兵力以保持大门畅通，要么需要保持足够的力量以抗击回来，因此，长城让围困城墙内的城市变得相对困难。

海外网友洛格斯拜的回答

Contrary to popular belief, the Great Wall of China is not only a defensive structure against invaders, but also an obstacle to trade with northern tribes in order to attack them in the future.

与普遍的看法相反，中国的长城不仅是抵御侵略者的防御结构，而且也是与北方部落进行贸易的障碍，以便日后对他们发起进攻。

The construction of the Great Wall started at the same time after Zhao conquered Linhu/Zhongshan, Yan conquered Donghu, and Qin conquered Yiqi/Hetao.

长城的修建是在赵国征服了临湖/中山国、燕国征服了东湖、秦国征服了义旗/河套之后同时开始的。

The Han Dynasty conquered the South Gobi Desert from the Huns, the Sui Dynasty defeated the West Turks, and the Ming Dynasty defeated the Tartars and Karka Mongols, continuing to extend the Great Wall to the 5000 km long miracle we see today.

汉朝从匈奴征服了南戈壁沙漠，隋朝战胜了西突厥，明朝战胜了鞑靼人和喀尔喀蒙古人，继续将长城延伸至我们今天看到的5000公里长的奇迹。

If you notice the timeline, most of the Great Wall was built after the decisive victory over the northern nomadic tribes, not before.

如果你注意到时间轴，长城的大部分是在战胜北方游牧部落取得决定性胜利之后建造的，而不是之前。

The vast northern grasslands lack scarce iron, salt and herbal resources, which are all necessities of war. All potential war materiel flowing to the northern tribes depended on trade, barter or smuggling. In the eyes of businessmen in the Central Plains, there is no international barrier to trade: where there is arbitrage, there is profit. Therefore, the northern tribes obtained a large number of metal weapons and potential wartime supplies through trade/barter/smuggling flows. When there are enough weapons and material reserves, the northern tribes will launch attacks or large-scale wars on the central plain.

广阔的北方草原缺少稀缺的铁、盐和草药资源，这些都是战争的必需品。流向北方部落的所有潜在战争物资都依赖于贸易、易货或走私。在中原商人眼中，贸易没有国际壁垒：有套利就有利润。因此，北方部落通过贸易/易货/走私流获得了大量金属武器和潜在的战时物资。当有足够的武器和物资储备时，北方部落将对中央平原发动袭击或大规模战争。

In order to reduce the resistance when fighting with the northern tribes, the Central Plains emperor needs to restrict or prohibit the northern tribes from mastering such strategic resources. The Great Wall is an ideal place to prevent war supplies from flowing to the north, so as to prepare for the attack.

为了在与北方部落作战时减少抵抗力，中原皇帝需要限制或禁止北方部落掌握此类战略资源，长城是阻止战争物资流向北方的理想之地，以便为进攻做好准备。

英国网友卡尔逊的回答

Historically, the city wall was used to stop the invaders. The Great Wall protects China from grassland nomads. Then there was Hadrian's wall in Rome, which was used to fight against troublesome northern tribes; Israel's separation wall along the West Bank and Gaza; Berlin Wall: obstacles along the demilitarized zone,; Belfast's "Peace Wall"; Finally, Trump's wall.

历史上，城墙是用来阻挡侵略者的。长城保护中国免受草原游牧民族的侵扰。然后是罗马的哈德良城墙，用来对抗麻烦的北方部落；以色列沿西岸和加沙的隔离墙；柏林墙：非军事区沿线的障碍物，；贝尔法斯特的“和平墙”；最后是特朗普的墙。

From the overall effect of thousands of years, the Great Wall is effective. If the city wall is useless, many kings will not build it, and the first emperor will not spend so much resources to connect it, after all, the cost is astronomical.

从几千年的总体效果来看，长城是有效的。如果城墙没有用处，许多国王就不会修建城墙，第一任皇帝也不会花费那么多资源将其连接起来，毕竟费用是天文数字。

For a long time, the Great Wall was very effective as a strategy, which could win space and time for smaller troops to ensure a long front. The wall did prevent or prevent many invasions.

在很长一段时间内，长城作为一种策略非常有效，可以为较小的部队争取空间和时间，以确保很长的战线，隔离墙确实阻止或阻止了许多入侵。

Helping reduce the size of troops: How many troops are needed to defend and maintain this long and dangerous border? The Great Wall reduced troops, logistics and costs, enabling the emperor to use it for other strategic purposes. Due to the long time and poor permeability, the Central Plains army did not know the time and place of the attack, nor how to respond to the correct location or prevent the enemy from escaping. The large area of land south of the Great Wall would be detrimental to agricultural or economic development. With the Great Wall, only a few people are needed to act as sentries and react first, and reinforcements can be quickly summoned.

帮助压缩兵力规模：需要多少兵力来保卫和维持这条漫长而危险的边境线？长城减少了军队、后勤和成本，使皇帝能够将其用于其他战略目的。由于时间长、渗透性差，中原军队不知道袭击的时间和地点，也不知道如何对正确的地点作出反应或阻止敌人逃跑，长城以南的大片土地将不利于农业或经济发展。有了长城，只需要少数人充当哨兵和第一反应，可以迅速召唤增援部队。

Communication: The city wall is connected, and each pillar can transmit information from far places through fire, smoke or horse express. In this way, the troops can learn about the situation reports inside and outside the Great Wall. The Great Wall combines powerful command and control with military intelligence.

通信：城墙是连通的，每个柱子都可以通过火光、烟雾或马匹快车从很远的地方传递信息。这样，部队就可以了解整个长城内外的情况报告。长城让强大的指挥和控制、军事情报结为一体。

Logistics: With the separation wall, logistics materials can be transported along the wall to provide supplies for the troops, which means that they have the advantage to maintain a long-term battle different from the past.

后勤：有了隔离墙，可以沿着隔离墙运送后勤物资，为部队提供补给，这意味着他们有优势维持与以往不同的长期战斗。

Since the enemy is mainly the cavalry of ethnic minorities, they have little mechanical means to build bridges, because they have little experience in conducting siege warfare on the defensive fortifications in the open grasslands. The enemy cannot know exactly how many troops are in front of or behind the wall.

由于敌人主要是少数民族骑兵，他们几乎没有机械手段来架桥，因为他们几乎没有在草原开阔地带的防御工事上进行围攻战的经验。敌人也无法确切知道有多少军队在墙前或躲在墙后。

Reduce the enemy's advantage: The cavalry will lose the advantage because the city wall is built in a position unfavorable to the cavalry or attack. The advanced high power projectiles on the wall will increase the combat advantage and have a longer range. Therefore, even if the number of aggressors is large, they will not have an advantage.

降低敌人优势：骑兵将失去优势，因为城墙修建在不利于骑兵或进攻的位置。墙壁上先进的高威力射弹将增加战斗优势，射程更远。因此，即使侵略者数量较大，他们也不会有优势。

Cost: The cost of building the fence has taken hundreds of years, as well as a lot of labor and costs. It is estimated that the Great Wall cost nearly 4 billion bricks. If it is laid end-to-end, it can circle the earth 36 times, with an estimated cost of 13 billion to 85 billion. Countless people will die as a result? But compared with the benefits of thousands of years, this is not worth mentioning.

成本：建造围墙的成本花费了数百年的时间，以及大量的劳动力和成本。据估计，长城花费了近40亿块砖头，如果端对端铺设，则可以绕地球36圈，估计费用为130亿至850亿，还有无数人因此死亡？但与几千年的收益相比，这不值一提。

The Great Wall is a symbol of Chinese civilization that is far more profound than the Tomb of the First Emperor of Qin. It is still the most symbolic and powerful. It clearly reminds the Chinese people that they can complete arduous projects by uniting. The Great Wall is the most symbolic and powerful national symbol.

长城是中国文明中远比秦始皇陵墓更深刻的象征，它仍然是最具标志性、最强大的，清楚地提醒着中国人，团结联合起来可以完成艰巨的工程，长城是最具象征性、最有力的国家标志。