“For the most part, the Chinese stayed in the background, rebuilding areas destroyed by U.S. bombs and manning anti-aircraft batteries. But perhaps their biggest role was preemptive: They made it clear that if U.S. ground troops invaded North Vietnam, then they would respond in kind.
Unlike during the Korean War, the United States yielded to this threat. “Their function is as a tripwire,” Moise says, “a warning to the Americans: ‘Don’t go too far… or you’ll be fighting us.’”
"This time, Johnson and his advisers paid close attention to the Chinese role. They were afraid that if the United States pushed too hard or attacked North Vietnam without restraint, they would have a replay of the Korean War. Johnson's critics later said that China was just bluffing, that the Chinese weren't serious about intervening. Harry Summers and other military writers criticized Johnson for allowing his fear of Chinese intervention to undermine his bombing campaign.
However, the new evidence from China suggests that Mao was seriously prepared to intervene. There was a secret agreement between Hanoi and Beijing that if the Americans launched a ground invasion of North Vietnam (at that time, the United States had restricted itself to a bombing campaign), China would send ground troops into North Vietnam and would not allow the United States to defeat Hanoi. If the Americans bombed North Vietnam, China would match the American military action by taking measures to protect North Vietnamese cities and to rebuild roads and bridges. They would also send anti-aircraft artillery units and army engineers to support North Vietnamese troops and help them deal with the air bombing pressure.
Meanwhile back in China, Mao was making preparations in anticipation of war with the United States. He relocated industries, universities, and research institutions in the coastal areas of eastern China to the mountainous areas of southwest China. He ordered his people to build anti-air shelters throughout China."
送去镀金的宝贝公子连灰都没留下。
从此失心疯般大炼钢铁，超英赶美，就是被美帝钢铁彻底打怕留下的后遗症，周边人谁都拉不住。
台海70年和平就是这么来的
老听到这么说，还没见到英文的报道。
还不是共产党在朝鲜被美国打怕了么，再也不敢随便越过什么线了。
越南国内一般都用“抵美救国抗战” Kháng chi?n ch?ng M? c?u n??c 来表达当年抗美战争。这个“国”也该是全越南而非北越。
你的理解则是故意地选择性理解，和楼主的思维是一样的。呵呵
https://www.history.com/news/vietnam-war-combatants
“For the most part, the Chinese stayed in the background, rebuilding areas destroyed by U.S. bombs and manning anti-aircraft batteries. But perhaps their biggest role was preemptive: They made it clear that if U.S. ground troops invaded North Vietnam, then they would respond in kind.
Unlike during the Korean War, the United States yielded to this threat. “Their function is as a tripwire,” Moise says, “a warning to the Americans: ‘Don’t go too far… or you’ll be fighting us.’”
“大部分情况下，中国人留在了幕后，重建了被美国炸弹和高空炮兵摧毁的地区。 但也许他们最大的作用是抢占先机：他们明确表示，如果美国地面部队入侵北越，那么他们将以实物回应。
与朝鲜战争不同，美国屈服于这一威胁。 莫伊斯说：“他们的功能就像绊索一样，向美国人发出警告：‘不要走太远……否则你会与我们作战。’”
https://www.wilsoncenter.org/article/china-contributed-substantially-to-vietnam-war-victory-claims-scholar
"This time, Johnson and his advisers paid close attention to the Chinese role. They were afraid that if the United States pushed too hard or attacked North Vietnam without restraint, they would have a replay of the Korean War. Johnson's critics later said that China was just bluffing, that the Chinese weren't serious about intervening. Harry Summers and other military writers criticized Johnson for allowing his fear of Chinese intervention to undermine his bombing campaign.
However, the new evidence from China suggests that Mao was seriously prepared to intervene. There was a secret agreement between Hanoi and Beijing that if the Americans launched a ground invasion of North Vietnam (at that time, the United States had restricted itself to a bombing campaign), China would send ground troops into North Vietnam and would not allow the United States to defeat Hanoi. If the Americans bombed North Vietnam, China would match the American military action by taking measures to protect North Vietnamese cities and to rebuild roads and bridges. They would also send anti-aircraft artillery units and army engineers to support North Vietnamese troops and help them deal with the air bombing pressure.
Meanwhile back in China, Mao was making preparations in anticipation of war with the United States. He relocated industries, universities, and research institutions in the coastal areas of eastern China to the mountainous areas of southwest China. He ordered his people to build anti-air shelters throughout China."
"这次，约翰逊及其顾问密切关注了中国的角色。他们担心，如果美国过分用力或无限制地进攻北越，他们将重演朝鲜战争。约翰逊的批评者后来说，中国只是虚张声势，中国人并不认真干预。哈里·萨默斯（Harry Summers）和其他军事作家批评约翰逊，让他担心中国的干预会破坏他的轰炸行动。
但是，来自中国的新证据表明，毛泽东已准备好进行干预。河内与北京之间达成一项秘密协议，即如果美国人向北越发动地面入侵（当时美国只限于轰炸行动），中国将向北越派遣地面部队，并且不允许美国打败河内。如果美国人轰炸北越，中国将采取措施保护北越的城市，并重建道路和桥梁，以配合美国的军事行动。他们还将派高射炮兵部队和陆军工程师支持北越部队，并帮助他们应对空袭压力。
与此同时，毛泽东回到中国时，正准备与美国发生战争。他将中国东部沿海地区的工业，大学和研究机构搬到了中国西南山区。他命令他的人民在中国各地建造防空洞。"
我觉得问我有无文献或媒体证据的人才有可能以中立心看清任何事情的人。
越战，不跟共军一般见识，就是不越过北越的界限，一样打败了越共，一兵一卒的不留，胜利的凯旋回国。当然，国军当年与共军决战，毅然凯旋至宝岛台湾。
胜利者从来如此，难怪美虱们持有这样的观点。
不是和北越人民军的战斗。人民军要过17度线得穿越共（即越南南方民族解放阵线，我看thrawn看来是不知道这一事实）马甲。这一事实本身就证明了共产党自己被美军打怕了，再也不敢像金日成过38度线那样过17度线了而不是相反！
你真看不懂么？也许吧。
区别是当年朝鲜进入过韩国多次，北越则打着越共人民军的旗号在南越作战。
区别是当年中国多次说过美军不能进入北朝鲜但美联军还是进了，而在越南中国的确先警告过美军跨过17度线（多种证明是说过）会有什么后果而最后不管何原因美军之后的确没有跨过17度线。
你再为美国和越共洗白，再黑我也无法改变已定的事实。
PS：”无非就是中共说啥你信啥“我好像没给过中共说得什么证据，给得全都是英文报告包括CIA的。CIA也等于”中共“吗？呵呵