请教一个句子结构

reginaer

把一段没读懂的阅读贴来，还请大家帮忙看看关于蓝亮部分的疑问，it指代的是什么，这部分在句子中是什么成分，又是什么意思。谢谢！

接自XDF阅读补充22段（第7篇）：

Yet if in the end neither service was the obvious victor, the principle of civilian dominance over the military clearly was. If there had ever been any danger that the United States military establishment might exploit, to the detriment of civilian control, the goodwill it enjoyed as a result of its victories in World War II, that danger disappeared in the interservice animosities engendered by the battle over unification.

reginaer

明白了，你说的对。谢谢！

ninihao

it指代United States military establishment，恩，后面你说的对，是同位语，解释civilian control的，但是我感觉to the detriment of civilian control不应该是插入语，他是接着danger说的 the danger to the detriment of civilian control，“that the United States military establishment might exploit”做定语修饰danger的，是他把这两个部分隔开了。

If引导的条件状语从句（其中包括一个定语从句修饰danger）,+ 同位语从句，＋主句。你感觉呢？

reginaer

谢谢楼主，我似乎明白点了。

句子的主干是：If there had ever been any danger..., that danger disappeared...

to the detriment of civilian control是插入语，the good will...是civilian control的同位语。

但是it是指代什么呢？是the United States military establishment 吗？

ninihao

If there had ever been any danger that the United States military establishment might exploit, to the detriment of civilian control, the goodwill it enjoyed as a result of its victories in World War II, that danger disappeared in the interservice animosities engendered by the battle over unification.

蓝色部分是定语修饰civilian control做插入语，因为前面已经提到了公民权（civilian control），美国政府一致认为人权就是goodwill，二战的胜利就是为人类遵循神旨为人权抗争最终取得胜利的完美诠释。

不过后面的那个that是特指这个danger才用的么？因为除此以外，我实在看不出来他到底是个什么成分。