pikeshot1600（美国）
Neither side could, or would try to, sustain any "invasion." Wars of the second half of the 20th century are illustrative. The two rivals would play out much of their conflict (over their vital interests) in other geographical locations, and by proxy as far as possible...Vietnam; Afghanistan.
The US and the USSR did that for forty-five years and never fought each other.
双方都承受不起或者不想承受入侵带来的损失。20世纪下半世纪的战争就说明了这点。在重大利益方面，两个对手尽可能通过代理人打仗，比如越战、阿富汗战争等。
美国和苏联的这个把戏玩了45年，从来没有直接交战。

General Michael Collins（爱尔兰）
Proxy war might be more likely but direct conflict is not impossible ... like in the Korean War, for example.
直接冲突是不可能的，更可能发生的是代理人战争...比如朝鲜战争...
pikeshot1600（美国）
In 1950, China was the proxy of the USSR. 1950年，中国是苏联的代理人。

okamido（美国）
Honestly, despite the fact that were are militarily and technologically superior, I believe that China would win as we no longer seem to have the will to do what it takes for victory.
老实说，尽管我们军事和技术上有优势，不过我认为中国会获胜，因为我们看似不再有获胜的意志。
Jake10（香港）
There's a lot of truth to this, but the outcome of the war would have a lot to do with reasons for it to happen. Before entering WWII, the US didn't have much of a warrior culture, but Japan woke a sleeping giant. If China attacked us, we'd win, but if we attacked China we'd lose. 你道出了很多真相，但是战争结果与战争爆发原因有很大关联。参加二战前，美国没有多少尚武文化，但日本唤醒了沉睡的巨人。如果中国攻击我们，我们会获胜；如果我们攻击中国，我们会失败。

fangqingming（中国）
korea war had proved that, both had not won, both had not lost. so , why not sit down and drink tea(or coffee)? let us to talk about bussiness.
朝鲜战争已经证明了，双方都没有赢，也没有输。所以，为什么不坐下来一起喝茶（咖啡）呢？还是谈生意要紧。
Charlie Bravo（美国）
Obviously that is the superior option overall. I believe the OP was simply a hypothetical question. Those with wisdom on both sides would naturally desire diplomacy and peace. 很明显，这是最棒的选择！我认为本话题只是假设性问题。双方的智者会渴望外交解决，渴望和平。

Scamp（美国）
Hopefully the US would never fall into the trap of getting in a land war in China.
This we could never win.
希望美国永远不要陷入与中国打陆战的圈套。这样的战争我们永远胜不了。

pikeshot1600（美国）
The definition (or the understanding) of "victory" is not what it was before the Cold War. Ask a professional military person what military success is now and it will not be dictating terms in the enemy's capital. More often it is identifying your most vital interests; deciding how much the cost is worth to address them, and holding you nose when you don't get all you wanted.