What you call "enemy" is, in this case, simply a fully independent nation. That is, one free to have goals and strategies that put its interest first. What you

What you call "enemy" is, in this case, simply a fully independent nation. That is, one free to have goals and strategies that put its interest first. What you call "allies" are subordinate nations, free to pursue their own interest as long as it doesn't conflict with the interest of the US. The US are a perfectly independent nation. So is China.