Ultimately, US foreign policy follows its citizen’s best interests. And, ignoring our occasional knee jerk reactions, most of our citizens are happy when we avoid war, expand individual rights and freedoms, increase trade, and maintain global stability.
China may not work out as expected, though. Who knows. I doubt anyone in the 70s believed that technology would advance far enough to allow an oppressive government to effectively control billions of people. Or, maybe the Chinese people are happy enough with their recently gained wealth that they accept being oppressed.